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A new method was developed for the synthesis of ethyl 3,6-diamino-4-aryl-5-cyanothieno[2,3-b]pyridine-2-carboxylates by the reaction of 4-aryl-2-amino-6-chloropyridine-3,5-dicarbonitriles with ethyl 2-mercaptoacetate. The synthesized compounds exhibit fluorescence both in solution and in the solid state. The emission maxima in benzene solution depend on the substituent and are in the range of 503–531 nm or from 498 to 541 nm in the solid state. For photoluminescence of ethyl 3,6-diamino-4-aryl-5-cyanothieno[2,3-b]pyridine-2-carboxylates, large Stokes shifts were observed: from 214 nm (13106 cm–1) in chloroform to 251 nm (14433 cm–1) in methanol. [ABSTRACT FROM AUTHOR]

Multicomponent condensation of cyanothioacetamide, carbonyl compounds, enamines and alkylating reagents initiated by the Knoevenagel reaction led to the formation of 2-thionicotinonitriles. The molecular and crystal structure of the prepared products was studied by single crystal X-ray diffraction method. [ABSTRACT FROM AUTHOR]

Background: This study aimed to assess the completion rate and postoperative bleeding incidence of endoscopic submucosal dissection (ESD) for gastric tumors under continuous antithrombotic therapy. Methods: A prospective observational study was conducted including 88 patients with 100 gastric lesions who underwent gastric endoscopic submucosal dissection (ESD) and received continuous antithrombotic therapy. Additionally, retrospective data on gastric ESD in 479 patients with 534 lesions who did not receive antithrombotic therapy were collected for comparison. Results: The en bloc resection rates (100% in the continuous antithrombotic therapy group vs. 100% in the non-antithrombotic therapy group) and complete resection rates (97.0% vs. 96.3%, respectively) were high and comparable between the groups. No significant differences were found in the specimen size or procedure time. Perforation rates were low (0% vs. 2.3%, respectively) and were not significantly different between the groups. However, postoperative bleeding occurred significantly more frequently in the continuous antithrombotic therapy group (10.2% vs. 4.2%, respectively) than in the non-antithrombotic therapy group. The subgroup analysis revealed a higher incidence of postoperative bleeding in patients receiving thienopyridine derivatives. Conclusions: Continuous administration of antithrombotic agents, especially thienopyridines, increased the risk of postprocedural hemorrhage following gastric ESD. These findings support the need for careful consideration of pharamcological management before ESD, aligning with the current guidelines. [ABSTRACT FROM AUTHOR]

The rate of microbial resistance has continued to rise significantly as the availability of new antibiotics has declined. A new series of pyridine and thienopyridine derivatives were designed, synthesized and tested as antimicrobial agents. The reaction of 4-bromo acetophenone and vetraldehyde (3,4-dimethoxy benzaldehyde) in ethanol and sodium hydroxide solution afforded the corresponding chalcone which was used as a suitable precursor to prepare a new series of pyridine derivatives. The treatment of the latter chalcone with 2-cyanothioacetamide afforded the corresponding pyridinethione which was used as a precursor to synthesize the targeted thienopyridine derivatives in good to excellent yield by the reaction with 2-chloro-N-arylacetamide derivatives, α-haloketones, methyl iodide or chloroacetonitrile in one or two steps. The structure of the synthesized compounds was confirmed chemically by their preparations with other pathways and their spectral data. The newly synthesized pyridine and thienopyridine derivatives exhibited good to strong antimicrobial activity against microbial strains E. coli, B. mycoides and C. albicans. With maximal antimicrobial activity against B. mycoides (33 mm) and C. albicans (29 mm), respectively, compounds 12a and 15 demonstrated the highest inhibition zone. Compound 12a prevented the growth of E. coli, at MIC level of 0.0195 mg/mL, and B. mycoides and C. albicans at MIC level below than 0.0048 mg/mL, respectively. Additionally, compound 15 prevented the visible growth of E. coli, B. mycoides, and C. albicans at MIC values of >0.0048, 0.0098, and 0.039 mg/mL, respectively. The relation between the chemical structure of the synthesized pyridine and thienopyridine compounds and their antimicrobial properties was discussed in the SAR study. [ABSTRACT FROM AUTHOR]

In the present work, a series of novel oxazolidinone derivatives containing thieno-pyridine ring system (11a–n) were synthesized in six steps. Synthesis of amino oxazolidinone scaffold (10) involved nucleophilic substitution of thienopyridine (4) with P-chloro-nitrobenzene (3) in dimethyl formamide at 65 °C give nitro compound (5) which was further reduced in catalytic hydrogenation condition using Raney-Nickel in isopropyl alcohol afforded amine (6). Reaction of compound (6) with 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (7) at mild reflux condition in isopropyl alcohol gives compound (8). Hydroxy amine compound (8) further undergo carbonyl insertion reaction with 1, 1'-carbonylbis(1H-imidazole) afforded oxazolidinone compound (9). The de-protection of phthalamide group of compound (9) carried by treating with aqueous solution of hydrazine hydrate in methanol at room temperature give compound (10). Finally, compound (10) reacts with acetyl chloride, carboxylic acid, sulfonyl chloride and chloro format by customary method provided amides, sulfonamide and carbamate derivative of (5S)-5-(aminomethyl)-3-[4-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-yl)phenyl]-1,3-oxazolidin-2-one. The developed synthetic approach was operationally simple and high yielding. The structures of the synthesized compounds were elucidated by IR, MS, 1H and 13C-NMR. Synthesized compounds (11a–n) were tested for antibacterial activity against a panel of Gram-positive bacteria comprising Staphylococcus aureus (ATCC5638), Streptococcus pyogenes (ATCC12344), Bacillus subtilis (ATCC6051), Bacillus pumilus (ATCC27142), and Enterococcus faecalis (NCIM5253). The investigation of antimicrobial screening data revealed that, most of the compounds tested have demonstrated sensible to good bacterial activity. In summary, preliminary results of activity indicate that, acetyl derivative (11a), methane sulfonamide derivative (11c) and p-toluene sulfonamide derivative (11e) found to be good activity and di-(methane sulfonamide) derivative (11d) showed comparable activity to reference drug substances. [ABSTRACT FROM AUTHOR]

Background & Aims: Endoscopic papillary balloon dilation (EPBD), a low-risk procedure for bleeding, has been suggested as an alternative to endoscopic sphincterotomy for papillary dilatation in patients undergoing endoscopic stone removal who are at a higher risk of bleeding. Several guidelines recommend that combination of two antiplatelet agents should be reduced to single antiplatelet therapy when endoscopic sphincterotomy is performed. However, there is no evidence that EPBD affects the risk of bleeding in patients receiving a combination of two antiplatelet agents; thus, we aimed to explore this problem. Methods: We included 31 patients who underwent EPBD for common bile duct stones at our hospital from May 2014 to August 2022 and received either a combination of two antiplatelet agents or single antiplatelet therapy prior to the procedure. The group receiving a combination of two antiplatelet agents included patients who underwent EPBT without antiplatelet therapy withdrawal or with a shorter withdrawal period than those recommended by the guidelines. Results: In the group that received a combination of two antiplatelet agents, one of the two antiplatelet agents used was thienopyridine. No bleeding was observed after EPBD in this study. We did not find any significant between-group differences in hemoglobin levels and rate of post-endoscopic retrograde cholangiopancreatography pancreatitis. Conclusions: In patients treated with a combination of two antiplatelet agents, EPBD could be safely performed without bleeding. Therefore, future prospective studies are warranted. [ABSTRACT FROM AUTHOR]

Heteromeric Tandem pore domain Acid Sensitive (TASK)-1/3 channels are critical to oxygen-sensing by carotid body type 1 cells, where hypoxia-induced inhibition of TASK-3 and/or TASK-1/3 potassium currents leads to voltage-gated calcium entry, exocytotic transmitter release and increases in carotid body afferent input responses that initiate corrective changes in breathing patterns. It was proposed that, in response to hypoxia, the AMP-activated protein kinase (AMPK) might directly phosphorylate and inhibit TASK channels, in particular TASK-3, but studies on rat type I cells questioned this view. However, sequence alignment identified a putative AMPK recognition motif in human (h) TASK-3, but not hTASK-1, with Ser 55 representing a potential phosphorylation site. We therefore studied the effects of five different AMPK activators on recombinant hTASK-3 potassium channels expressed in human embryonic kidney (HEK)-293 cells. Two structurally unrelated AMPK activators, the thienopyridine A-769662 (100-500 µM) and the benzimidazole 991 (3-30 µM) inhibited hTASK-3 currents in a concentration-dependent manner, while the 4-azabenzimidazole MK-8722 (3-30 µM) partially inhibited hTASK-3 at concentrations above those required for maximal AMPK activation. By contrast, the 4-azabenzimidazole, BI-9774 (10-100 µM; a closely related analogue of MK8722) and the pro-drug AICA-riboside (1 mM; metabolised to ZMP, an AMP-mimetic) had no significant effect on hTASK-3 currents at concentrations sufficient to maximally activate AMPK. Importantly, A-769662 (300 µM) also inhibited hTASK-3 channel currents in HEK-293 cells that stably over-expressed an AMPK-β1 subunit mutant (S108A) that renders AMPK insensitive to activators that bind to the Allosteric Drug and Metabolite site, such as A-769662. We therefore identify A-769662 and 991 as novel hTASK-3 channel inhibitors and provide conclusive evidence that AMPK does not regulate hTASK-3 channel currents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Copyright of Revista Argentina de Cardiología is the property of Sociedad Argentina de Cardiologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AimsIn the dual antiplatelet therapy (DAPT) study, continued thienopyridine beyond 12 months after drug-eluting stent placement was associated with increased mortality compared with placebo. We sought to evaluate factors related to mortality in randomized patients receiving either drug-eluting or bare metal stents in the DAPT study.Methods and resultsPatients were enrolled after coronary stenting, given thienopyridine and aspirin for 12 months, randomly assigned to continued thienopyridine or placebo for an additional 18 months (while taking aspirin), and subsequently treated with aspirin alone for another 3 months. A blinded independent adjudication committee evaluated deaths. Among 11 648 randomized patients, rates of all-cause mortality rates were 1.9 vs. 1.5% (continued thienopyridine vs. placebo, P = 0.07), cardiovascular mortality, 1.0 vs. 1.0% (P = 0.97), and non-cardiovascular mortality, 0.9 vs. 0.5% (P = 0.01) over the randomized period (Months 12-30). Rates of fatal bleeding were 0.2 vs. 0.1% (P = 0.81), and deaths related to any prior bleeding were 0.3 vs. 0.2% (P = 0.36), Months 12-33). Cancer incidence did not differ (2.0 vs. 1.6%, P = 0.12). Cancer-related deaths occurred in 0.6 vs. 0.3% (P = 0.02) and were rarely related to bleeding (0.1 vs. 0, P = 0.25). After excluding those occurring in patients with cancer diagnosed before enrolment, rates were 0.4 vs. 0.3% (P = 0.16).ConclusionBleeding accounted for a minority of deaths among patients treated with continued thienopyridine. Cancer-related death in association with thienopyridine therapy was mainly not related to bleeding and may be a chance finding. Caution is warranted when considering extended thienopyridine in patients with advanced cancer.Trial registrationclinicaltrials.gov Identifier: NCT00977938.

The study aimed to compare the efficacy and safety outcome associated with a short and a prolonged duration of thienopyridine therapy in patients with chronic kidney disease (CKD) after coronary stenting. We systematically searched PubMed, EMBASE and the Cochrane Library from their inception to 1 January 2019 for studies comparing short and prolonged thienopyridine therapy in patients with CKD. Ischemic and bleeding events were considered as the clinical endpoints in this analysis. Odds Ratios (OR) with 95% confidence intervals (CIs) were used as estimates of effect size in random-effect models. Seven studies comprising a total of 17,628 CKD patients were included in the evaluation. Prolonged duration of thienopyridine use, when compared to short-term thienopyridine, was associated with reduced risk of all-cause mortality (odds ratio 0.75, 95% confidence interval: 0.70–0.81, P< .001) and stent thrombosis (OR: 0.54, 95% CI 0.32 to 0.89; P< .001), but the odds of myocardial infarction (OR: 0.91, 95% CI: 0.77–1.07; P = .23) and stroke (OR: 0.91, 95% CI 0.73 to 1.13; P = .38) did not differ according to different duration of thienopyridine. As for bleeding events, long-term thienopyridine therapy did not significantly increase the bleeding (OR: 0.95, 95% CI 0.79 to 1.14; P = .58). In these patients with CKD following PCI, prolonged thienopyridine therapy compared with short-term therapy, was associated with reduced all-cause mortality and stent thrombosis, without any significant difference in myocardial infarction, stroke, and bleeding. Thienopyridine prolongation decisions for CKD patients should be individualized after careful consideration of the benefit–risk balance.

Ethyl 5-cyano-1,6-dihydro-2-methyl-4-(2'-thienyl)-6-thioxonicotinate ( A ) was synthesized and reacted with ethyl chloroacetate in the presence of sodium acetate or sodium carbonate to give ethyl 5-cyano-6-((2-ethoxy-2-oxoethyl)thio)-2-methyl-4-(2'-thienyl)nicotinate ( 1a ) or its isomeric thieno[2,3- b ]pyridine 2a . 3-Aminothieno[2,3- b ]pyridine-2-carboxamide 2b was also synthesized by the reaction of A with 2-chloroacetamide. The reaction of 1a with hydrazine hydrate in boiling ethanol gave acethydrazide 3 . Heating ester 1a with hydrazine hydrate under neat conditions afforded 3-amino-1 H -pyrazolo[3,4- b ]pyridine 10 . Compounds 2b , 3, and 10 were used as precursors for synthesizing other new thieno[2,3- b ]pyridines and pyrazolo[3,4- b ]pyridines containing mainly the ethyl nicotinate scaffold. Structures of all new compounds were confirmed by elemental and spectral analyses. Most of the obtained compounds were evaluated for their insecticidal activity toward the nymphs and adults of Aphis gossypii (Glover,1887). Some compounds such as 4 , 9b, and 9c showed promising results. The effect of some sublethal concentrations, less than LC 50 , of compounds 4 , 9b, and 9c on the examined Aphis was subjected to a further study. The results demonstrated that exposure of A. gossypii nymphs to sublethal concentrations of compounds 4 , 9b, and 9c had noticeable effects on their biological parameters, i.e., nymphal instar duration, generation time, and adult longevity. The highest concentration C1 of all three compounds increased the nymphal instar duration and generation time and decreased adult longevity and vice versa.

Antithrombotic thienopyridines, such as clopidogrel and prasugrel, are prodrugs that undergo a metabolic two-step bioactivation for their pharmacological efficacy. In the first step, a thiolactone is formed, which is then converted by cytochrome P450-dependent oxidation via sulfenic acids to the active thiol metabolites. These metabolites are the active compounds that inhibit the platelet P2Y12 receptor and thereby prevent atherothrombotic events. Thus far, described biocatalytic and chemical synthesis approaches to obtain active thienopyridine metabolites are rather complex and suffer from low yields. In the present study, several unspecific peroxygenases (UPOs, EC 1.11.2.1) known to efficiently mimic P450 reactions in vitro—but requiring only hydroperoxide as oxidant— were tested for biocatalytic one-pot syntheses. In the course of the reaction optimization, various parameters such as pH and reductant, as well as organic solvent and amount were varied. The best results for the conversion of 1 mM thienopyridine were achieved using 2 U mL−1 of a UPO from agaric fungus Marasmius rotula (MroUPO) in a phosphate-buffered system (pH 7) containing 5 mM ascorbate, 2 mM h−1 H2O2 and 20% acetone. The preparation of the active metabolite of clopidogrel was successful via a two-step oxidation with an overall yield of 25%. In the case of prasugrel, a cascade of porcine liver esterase (PLE) and MroUPO was applied, resulting in a yield of 44%. The two metabolites were isolated with high purity, and their structures were confirmed by MS and MS2 spectrometry as well as NMR spectroscopy. The findings broaden the scope of UPO applications again and demonstrate that they can be effectively used for the selective synthesis of metabolites and late-state diversification of organic molecules, circumventing complex multistage chemical syntheses and providing sufficient material for structural elucidation, reference material, or cellular assays. [ABSTRACT FROM AUTHOR]

[Display omitted] Neural differentiation is triggered by the activation of multiple signaling pathways initiated by various neurotrophic factors. An elucidation of these mechanisms is anticipated to facilitate the prevention of diseases and the development of novel therapeutic approaches. Alternative small-molecule inducers for neuroscience studies are required instead of protein-based reagents for more efficient and convenient experiments. We demonstrated that small molecules of thieno[2,3- b ]pyridine derivatives that induce neural differentiation, compounds 3a and 9a in particular, exhibited significant neuritogenic activity in rat pheochromocytoma (PC12) cells. Moreover, 3a displayed pronounced fluorescence and a discernible Stokes shift. Furthermore, the outcome of the experiment conducted on the NGF-insensitive clones of rat PC12 cells, and the results of the intercellular uptake analyses suggested that the 3a -mediated activation of neural differentiation occurred independently of the TrkA receptor. Therefore, 3a portrays potential applicability both as a small molecule reagent to replace novel neurotrophic factors and as a potent fluorescent reagent for various techniques, including bioimaging. [ABSTRACT FROM AUTHOR]

BackgroundHemostatic benefits of platelet transfusions in thienopyridine-treated acute coronary syndrome (ACS) patients may be compromised by residual metabolite in circulation.ObjectivesTo estimate the earliest time after a prasugrel loading-dose when added platelets are no longer inhibited by prasugrel's active metabolite.MethodsBaseline platelet reactivity of healthy subjects (n=25, 30 ± 5 years, 68% male) on ASA 325 mg was tested using maximum platelet aggregation (MPA, ADP 20 μm) and VerifyNow(®) P2Y12 and was followed by a 60 mg prasugrel loading-dose. At 2, 6, 12 and 24 h post-dose, fresh concentrated platelets from untreated donors were added ex-vivo to subjects' blood, raising platelet counts by 0% (control), 40%, 60% and 80%. To estimate the earliest time when prasugrel's active metabolite's inhibitory effect on the added platelets ceases, platelet function in supplemented samples was compared across time-points to identify the time when effect of supplementation on platelet function stabilized (i.e. the increase in platelet reactivity was statistically similar to that at the next time-point).ResultsSupplemented samples showed concentration-dependent increases in platelet reactivity vs. respective controls by both MPA and VerifyNow(®) at all assessment time-points. For each supplementation level, platelet reactivity showed a sharp increase from 2 to 6 h but was stable (P=NS) between 6 and 12 h.ConclusionsThe earliest measured time when supplemented platelets were not inhibited by circulating active metabolite of prasugrel was 6 h after a prasugrel loading-dose. These findings may have important implications for prasugrel-treated ACS patients requiring platelet transfusions during surgery.

Background/AimsCurrent guidelines recommend withholding antiplatelets for 5–7 days before high-risk endoscopic procedures. We investigated whether this reduces post-endoscopic submucosal dissection (ESD) bleeding.Methods : Gastric ESD cases with antiplatelets were retorospectively reviewed. Withholding antiplatelets for 5–7 days before ESD was defined as cessation and 0–4 days as continuation. The rate and risk of post-ESD bleeding according to the types and cessation of antiplatelets were assessed.Results : Among the 215 patients (117 adenoma and 98 early gastric cancer), 161 patients were on single (94 aspirin, 56 thienopyridine, and 11 other agents), 51 on dual, and 3 on triple antiplatelets. Post-ESD bleeding rates were 12.8% in aspirin users, 3.6% in thienopyridine, 27.5% in dual, 33.3% in triple therapy, and 9.7% in the cessation and 15.0% in the continuation group. Multiple antiplatelets (odds ratio [OR], 2.41; 95% confidence interval [CI], 1.01 to 5.76) and specimen size ≥ 5.5 cm (OR, 2.84; 95% CI, 1.04 to 7.73) were the risk of bleeding, while continuation of thienopyridine (OR, 0.23; 95% CI, 0.05 to 1.09) and antiplatelets (OR, 1.83; 95% CI, 0.68 to 4.94) did not increase the risk of bleeding.Conclusion : sContinuing thienopyridine and aspirin did not increase the risk of post-ESD. Multiple antiplatelet therapy and a large specimen size were independent risk factors of post-ESD bleeding.

Prasugrel is a third-generation thienopyridine that provides earlier onset of action, has a reduced probability of insensitivity to the drug, a greater degree of inhibition of ADP-induced platelet aggregation compared to clopidogrel. Prasugrel should be proscribed to the following categories of patients: 1) patients with ST-segment elevation ACS who undergo primary percutaneous coronary interventions; 2) patients with ST-segment elevation ACS, who underwent thrombolysis, but scheduled to receive delayed PCI; 3) patients with non ST-segment elevation ACS with a known coronary anatomy, which are scheduled to receive PCI; 4) patients who had stent thrombosis due to clopidogrel resistance. Prasugrel may be considered in patients with stable coronary artery disease if they are at high risk of stent thrombosis after a planned PCI. One should avoid prescribing this drug to patients with a history of stroke or TIA, as well as to patients 75 years or older, with body weight less than 60 kg. The best results for the use of prasugrel are expected in patients younger than 60 years old, with ST segment elevation MI, concomitant diabetes mellitus, creatinine clearance of at least 60 ml / min. The article also discusses current ideas about the «de-escalation» of prasugrel therapy, presents recently published data on the comparative efficacy and safety of prasugrel and ticagrelor.

The study aimed to compare the efficacy and safety outcome associated with a short and a prolonged duration of thienopyridine therapy in patients with chronic kidney disease (CKD) after coronary stenting. We systematically searched PubMed, EMBASE and the Cochrane Library from their inception to 1 January 2019 for studies comparing short and prolonged thienopyridine therapy in patients with CKD. Ischemic and bleeding events were considered as the clinical endpoints in this analysis. Odds Ratios (OR) with 95% confidence intervals (CIs) were used as estimates of effect size in random-effect models. Seven studies comprising a total of 17,628 CKD patients were included in the evaluation. Prolonged duration of thienopyridine use, when compared to short-term thienopyridine, was associated with reduced risk of all-cause mortality (odds ratio 0.75, 95% confidence interval: 0.70–0.81, P<.001) and stent thrombosis (OR: 0.54, 95% CI 0.32 to 0.89; P<.001), but the odds of myocardial infarction (OR: 0.91, 95% CI: 0.77–1.07; P =.23) and stroke (OR: 0.91, 95% CI 0.73 to 1.13; P =.38) did not differ according to different duration of thienopyridine. As for bleeding events, long-term thienopyridine therapy did not significantly increase the bleeding (OR: 0.95, 95% CI 0.79 to 1.14; P =.58). In these patients with CKD following PCI, prolonged thienopyridine therapy compared with short-term therapy, was associated with reduced all-cause mortality and stent thrombosis, without any significant difference in myocardial infarction, stroke, and bleeding. Thienopyridine prolongation decisions for CKD patients should be individualized after careful consideration of the benefit–risk balance. [ABSTRACT FROM AUTHOR]

Ticlopidine hydrochloride (1⋅HCl, Ticlid™) is a prodrug that, through bioactivation by cytochrome P450 (CYP), interacts with the P2Y12 receptor ADP inhibiting platelet aggregation. This prodrug mediated by a multistep biochemical process led to the formation of active metabolic intermediates. In this work, an eco‐friendly and efficient protocol for the formation of 2‐chloroticlopidine (2) using 1⋅HCl and oxone in aqueous methanol media via an unprecedented formation of reactive thienopyridine intermediate 2‐chloro‐5‐(2‐chlorobenzyl)‐4,5,6,7‐tetrahydrothieno[3,2‐c]pyridine 5‐oxide (4) was developed. The key to success of 4 is the oxidation of tertiary amines to N‐oxides, followed by mono‐chlorination at the 2‐position of the thiophene ring by oxidation of the chloride counterion of this prodrug. In addition, we use the 1D and 2D NMR techniques as a tool to monitor reaction progress, and for assigning the signals of all compounds involved, especially for the novel thienopyridine 4. [ABSTRACT FROM AUTHOR]

Antithrombotic thienopyridines, such as clopidogrel and prasugrel, are prodrugs that undergo a metabolic two-step bioactivation for their pharmacological efficacy. In the first step, a thiolactone is formed, which is then converted by cytochrome P450-dependent oxidation via sulfenic acids to the active thiol metabolites. These metabolites are the active compounds that inhibit the platelet P2Y12 receptor and thereby prevent atherothrombotic events. Thus far, described biocatalytic and chemical synthesis approaches to obtain active thienopyridine metabolites are rather complex and suffer from low yields. In the present study, several unspecific peroxygenases (UPOs, EC 1.11.2.1) known to efficiently mimic P450 reactions in vitro—but requiring only hydroperoxide as oxidant—were tested for biocatalytic one-pot syntheses. In the course of the reaction optimization, various parameters such as pH and reductant, as well as organic solvent and amount were varied. The best results for the conversion of 1 mM thienopyridine were achieved using 2 U mL−1 of a UPO from agaric fungus Marasmius rotula (MroUPO) in a phosphate-buffered system (pH 7) containing 5 mM ascorbate, 2 mM h−1 H2O2 and 20% acetone. The preparation of the active metabolite of clopidogrel was successful via a two-step oxidation with an overall yield of 25%. In the case of prasugrel, a cascade of porcine liver esterase (PLE) and MroUPO was applied, resulting in a yield of 44%. The two metabolites were isolated with high purity, and their structures were confirmed by MS and MS2 spectrometry as well as NMR spectroscopy. The findings broaden the scope of UPO applications again and demonstrate that they can be effectively used for the selective synthesis of metabolites and late-state diversification of organic molecules, circumventing complex multistage chemical syntheses and providing sufficient material for structural elucidation, reference material, or cellular assays.

A selective transformation of clopidogrel hydrogen sulfate (CLP) by reactive halogen species (HOX) generated from peroxymonosulfate (PMS) and sodium halide (NaX) is described. Other sustainable oxidants as well as different solvents have also been investigated. As result of this study, for each sodium salt the reaction conditions were optimized, and four different degradation products were formed. Three products were halogenated at C-2 on the thiophene ring and have concomitant functional transformation, such as N-oxide in the piperidine group. A halogenated endo-iminium product was also observed. With this condition, a fast preparation of known endo-iminium clopidogrel impurity (new counterion) was reported as well. The progress of the reaction was monitored using nuclear magnetic resonance spectroscopy as an analytical tool and all the products were characterized by 1D-, 2D-NMR and HRMS.

Abstract Urea transporters (UTs) play an important role in the urine concentrating mechanism and are recognized as novel targets for developing small molecule inhibitors with salt-sparing diuretic activity. Thienoquinoline derivatives, a class of novel UT-B inhibitors identified by our group, play a significant diuresis in animal model. However, the poor solubility and low bioavailability limited its further development. To overcome these shortcomings, the structure modification of thienoquinoline was carried out in this study, which led to the discovery of novel thienopyridine derivatives as specific urea transporter inhibitors. Further optimization obtained the promising preclinical candidate 8n with not only excellent inhibition effect on urea transporters and diuretic activity on rat model, but also suitable water solubility and Log P value. Graphical abstract Image 1 Highlights • Discovery of a novel structural type of urea transporter inhibitor with thienopyridine scaffold through SAR study of PU48. • Most of the thienopyridines showed significant inhibition activity on UT-B in vitro. • Compound 8n exhibited potent activities both in vitro and in vivo. • Compound 8n showed predictable higher water solubility than PU48. [ABSTRACT FROM AUTHOR]

In this study, 15 commercial acidic drugs have been evaluated for pancreatic lipase (PL) inhibitory activity using an in vitro spectrophotometric method. The acidity was the basis of selection, since most PL inhibitors exhibit acidic groups and high lipophilicity. Orlistat was the robust reference agent for potency and efficacy determinations. In comparison to the cisplatin, the evaluation of the antineoplastic activities of selected drugs in a panel of colorectal cancer cell lines (HT‐29, HCT‐116, SW620, CACO‐2, and SW480) and normal periodontal ligament fibroblasts for safety examination was performed by using a sulforhodamine procuring ascorbic acid as a reference in diphenyl‐2‐picryl‐hydrazyl assay of radical scavenging properties was performed. This research revealed three highly acidic pharmacological classes with reasonable PL inhibitory activity in comparison to orlistat out of 15 selected drugs, namely sulfonylureas, fluoroquinolones, and proton pump inhibitors. Docking studies supported the hypothesis of a selection based on acidity, since it showed that the sulfonamide acid group (glyburide) is a remarkably potent interacting group with the enzyme. Failing to fulfill other structure‐activity relationship requirements (lipophilicity) led to weak activity. Since the drugs are of different chemical classes with unknown mechanisms, they showed diverse antiproliferative activity. Some drugs such as atorvastatin and gemifloxacin showed higher antiproliferative activity than cisplatin with high‐safety profiles against SW620 and SW480 cell lines, respectively, whereas lansoprazole and clopidogrel revealed comparable activity to cisplatin against HCT‐116 and SW480, respectively. Unfortunately, selected tested drugs exhibited negligible radical scavenging activity versus ascorbic acid. Hit, Lead & Candidate Discovery [ABSTRACT FROM AUTHOR]

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Abstract Background and objectives Vicagrel, a novel thienopyridine antiplatelet agent, is an analogue of clopidogrel in development for the treatment of acute coronary syndromes. This study investigated the pharmacokinetic properties of vicagrel after single oral dosing with a direct comparison with clopidogrel in healthy Chinese subjects in the first two phase I clinical studies. The relationship between the exposure to the active metabolite and the platelet reactivity was also assessed for vicagrel. Methods Study A was a single-ascending-dose study of vicagrel (5–75 mg) compared with clopidogrel (75 mg) in 67 healthy volunteers. Study B was a randomized, two-period, crossover, loading-dose study of vicagrel 20 mg compared with clopidogrel 300 mg in 12 healthy subjects. Plasma concentrations of three common metabolites of vicagrel and clopidogrel, the active thiol metabolite H4, the inactive thiol metabolite H3, and the S -methylated form of H3 (SM3, the major metabolite of vicagrel), were determined using a validated UHPLC–MS/MS method. The relationship between the AUC 0−t of active H4 and the P2Y 12 reaction units at 4 h after administration of vicagrel was investigated. Blood concentrations of vicagrel were determined after a single oral administration of vicagrel 25 mg to two healthy Chinese subjects. Results In the single-ascending-dose study, vicagrel was metabolized rapidly with the median t max for the three metabolites, namely, H4, H3, and SM3, ranging from 0.25–1.75 h. The pharmacokinetics of the three metabolites for vicagrel were linear across the dose range of 5–75 mg, with the mean C max and AUCs for H4 and H3 increasing in an approximately 1:1 dose-proportional manner and for SM3 increasing in a <1:1 dose-proportional manner. The median t max for active H4 in the vicagrel 5 mg group was slightly shorter than that in the clopidogrel 75 mg group (0.50 versus 0.75 h). The mean AUC 0−t for H4 in the vicagrel 5 mg group was similar to that in the clopidogrel 75 mg group (11.7 versus 11.8 ng∙h/mL). The AUC 0−t of active H4 was apparently associated with the P2Y 12 reaction units at 4 h for vicagrel. In the loading-dose study, for active H4, the median t max was slightly shorter (0.50 versus 0.75 h) and the mean AUC 0−t was 29% higher in the vicagrel 20 mg group than those in the clopidogrel 300 mg group. After a single oral administration of vicagrel 25 mg to 2 subjects, vicagrel was detected in blood but in very low concentrations. Conclusions Vicagrel was rapidly and extensively metabolized, and the levels of the parent drug in circulation were very low. The pharmacokinetics of the three metabolites of vicagrel were linear and predictable across the dose range of 5–75 mg. The AUC of active H4 was apparently associated with the P2Y 12 reaction units for vicagrel. For active H4, vicagrel 5 mg produced similar exposure (AUC) with more rapid appearance compared with clopidogrel 75 mg, and vicagrel 20 mg produced even slightly higher exposure (AUC) with more rapid appearance compared with clopidogrel 300 mg in humans. Trial Registration: CTR20150346, CTR20160379. Graphical abstract (A) Metabolic pathways of clopidogrel and vicagrel in humans. (B) Mean plasma concentrations of active H4 after a single oral administration of vicagrel 5 mg or clopidogrel 75 mg in healthy Chinese subjects. (C) Assessment of dose proportionality for AUC 0−t of active H4 after single oral administration of vicagrel. Unlabelled Image [ABSTRACT FROM AUTHOR]

Clopidogrel response variability has been identified in cats. In humans, evidence suggests that variable clopidogrel active metabolite (CAM) generation is the primary explanation for clopidogrel response variability with differences in body weight, sex, and variable metabolism of clopidogrel primarily due to polymorphisms of the gene encoding cytochrome P450 (CYP) 2C19 as some proposed mechanisms. The aim of this study was to evaluate whether variation in CAM concentrations exists in healthy cats and what the cause of such variation might be. Nineteen healthy cats were given 18.75 mg clopidogrel by mouth. Blood was collected 2 hr later. Plasma CAM concentrations were measured using high performance liquid chromatography and tandem mass spectrometry. Clopidogrel metabolism was estimated by calculating CAM metabolic ratio. DNA was collected, and feline CYP2C genotyping was performed. The cats demonstrated high interindividual variation of plasma CAM concentrations. Approximately 69% of this interindividual variation was primarily explained by differences in clopidogrel metabolism as measured by CAM metabolic ratio with some influence by sex but not by weight. A single nucleotide polymorphism was identified in the feline CYP2C gene that explained in part individual differences in CAM metabolic ratio and CAM plasma concentrations. [ABSTRACT FROM AUTHOR]

As a part of ongoing studies in developing new anticancer agents, novel 1,2-dihydropyridine 4, thienopyridine 5, isoquinolines 6–20, acrylamide 21, thiazolidine 22, thiazoles 23–29 and thiophenes 33–35 bearing a biologically active quinoline nucleus were synthesized. The structure of newly synthesized compounds was confirmed on the basis of elemental analyses and spectral data. All the newly synthesized compounds were evaluated for their cytotoxic activity against the breast cancer cell line MCF7. 2,3-Dihydrothiazole-5-carboxamides 27, 25, 4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (34), 1,2-dihydroisoquinoline-7-carbonitrile (7), 5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene-3-carboxamide (35), 1,2-dihydroisoquinoline-7-carbonitrile (6), 2-cyano-3-(dimethylamino)-N-(quinolin-3-yl)acrylamide (21), 1,2-dihydroisoquinoline-7-carbonitriles (11) and (8) exhibited higher activity (IC50 values of 27–45 μmol L–1) compared to doxorubicin (IC50 47.9 μmol L–1). LQ quinolin-3-yl)-1,2-dihydroisoquinoline-7-carbonitrile (12), 2-thioxo-2,3-dihydrothiazole-5-carboxamide (28) and quinolin-3-yl)-1,2-dihydroisoquinoline-7-carbonitrile (15) show activity comparable to doxorubicin, while (quinolin-3-yl)-1,2-dihydroisoquinoline-7-carbonitrile (9), 2,3-dihydrothiazole-5-carboxamide (24), thieno [3,4-c] pyridine-4(5H)-one (5), cyclopenta[b]thiophene-3-carboxamide (33) and (quinolin-3-yl)-6-stryl-1,2-dihydroisoquinoline-7-carbonitrile (10) exhibited moderate activity, lower than doxorubicin.

Patrick Goldstein,1 Niccolò Grieco,2 Hüseyin Ince,3,4 Nicolas Danchin,5 Yvonne Ramos,6 Jochen Goedicke,7 Peter Clemmensen8,9 On behalf of the MULTIPRAC study investigators 1Emergency Department, Lille Regional University Hospital, Lille, France; 2Department of Cardiology, Hospital Niguarda Cà Granda Milano, Milan, Italy; 3Internal Medicine Centre, Cardiology Department, Rostock University Clinic, Rostock, Germany; 4Department of Cardiology, Vivantes Klinikum im Friedrichshain and Am Urban, Berlin, Germany; 5Department of Cardiology, European Hospital Georges-Pompidou, Paris, France; 6Medical Department, Daiichi Sankyo Europe, Munich, 7Medical Department, Lilly Deutschland GmbH, Bad Homburg, Germany; 8Department of Medicine, Division of Cardiology, Rigshospitalet Copenhagen University Hospital, 9Department of Medicine, Division of Cardiology, Nykoebing F Hospital, Copenhagen, Denmark Aim: MULTIPRAC was designed to provide insights into the use and outcomes associated with prehospital initiation of antiplatelet therapy with either prasugrel or clopidogrel in the context of primary percutaneous coronary intervention. After a previous report on efficacy and safety outcomes during hospitalization, we report here the 1-year follow-up data, including cardiovascular (CV) mortality. Methods and results: MULTIPRAC is a multinational, prospective registry of patients with ST-elevation myocardial infarction (STEMI) from 25 hospitals in nine countries, all of which had an established practice of prehospital start of dual antiplatelet therapy in place. The key outcome was CV death at 1 year. Among 2,036 patients followed-up through 1 year, 49 died (2.4%), 10 during the initial hospitalization and 39 within 1 year after hospital discharge. The primary analysis was based on the P2Y12-inhibitor, used from prehospital loading dose through hospital discharge. Prasugrel (n=824) was more commonly used than clopidogrel (n=425). The observed 1-year rates for CV death were 0.5% with prasugrel and 2.6% with clopidogrel. After adjustment for differences in baseline characteristics, treatment with prasugrel was associated with a significantly lower risk of CV death than treatment with clopidogrel (odds ratio 0.248; 95% confidence interval 0.06–0.89). Conclusion: In STEMI patients from routine practice undergoing primary angioplasty, who were able to start oral antiplatelet therapy prehospital, treatment with prasugrel as compared to clopidogrel was associated with a lower risk of CV death at 1-year follow-up. Keywords: upstream treatment, P2Y12-inhibitor, dual antiplatelet therapy, primary percutaneous coronary intervention, observational

Considering the thiophene unit as an electron-rich heterocycle, it is investigated with the aim of elucidating its potential efficiency for solar cell application. With the introduction of active substituents such as COOEt, CONH2 and CN into the thiophene segment, three novel thieno pyridine sensitizers (6a–c), based on donor-acceptor D-π-A construction, are designed and synthesized. The effect of the anchoring groups is investigated based on their molecular orbital’s (MO’s) energy gap (Eg). The electrostatic interaction between the synthesized dyes and metal nanoparticles, namely gold, silver and ruthenium, is believed to improve their performance as organic sensitizers. The dye-sensitized solar cells (DSSCs) are manufactured using the novel diazenyl pyridothiophene dyes, along with their metal nanoparticles conjugates as sensitizers, and were examined for efficiency improvement. Accordingly, using this modification, the photovoltaic performance was significantly improved. The promising results of conjugate (6b/AgNPs), compared with reported organic and natural sensitizers (JSC (1.136 × 10−1 mA/cm2), VOC (0.436 V), FF (0.57) and η (2.82 × 10−2%)), are attributed to the good interaction between the amide, methyl, amino and cyano groups attached to the thiophene pyridyl scaffolds and the surface of TiO2 porous film. Implementation of a molecular modeling study is performed to predict the ability of the thiophene moiety to be used in solar cell applications.

Drugs which inhibit platelet function are commonly used to prevent blood clot formation in patients with Acute Coronary Syndromes (ACS) or those at risk of stroke. The thieno[3,2- c ]pyridine class of therapeutic agents, of which clopidogrel is the most commonly used, target the P2Y 12 receptor, and are often used in combination with acetylsalicylic acid (ASA). Six thieno[2,3- b ]pyridine were assessed for in vitro anti-platelet activity; all derivatives showed effects on both platelet activation and aggregation, and showed synergy with ASA. Some compounds demonstrated greater activity when compared to clopidogrel. These compounds, therefore, represent potential novel P2Y 12 inhibitors for improved treatment for patients. [ABSTRACT FROM AUTHOR]

Virtual high throughput screening of a large compound library against the regulatory enzyme phospholipase C (PLC) led to the discovery of the thieno[2,3-b]pyridine-2-carboxamides as potential inhibitors. Subsequent biological testing verified the antiproliferative activity of this compound class. Morphology and motility assays, using a number of triple negative breast cancer cell lines, led to the conclusion that PLC is the most probable biomolecular target. Using a combination of computer-aided drug design and synthesis, further analogues have been prepared and tested for their antiproliferative activity, allowing a comprehensive SAR to be developed. Numerous analogues with low nano-molar growth inhibition against various cancers have been prepared. SAR studies suggest that the core structure can be fine-tuned to specific cancers, potentially due to enzyme/isoform specificity. Additionally, mouse xenograft assays showed significant reduction in tumour size after treatment, whilst showing no adverse effects to non-cancerous mice. Here, we report on our recent development of novel thienopyridines and derivatives, expanding the SAR against PLC, and our efforts to prepare potent, soluble, and bioavailable compounds.

Patients with ischemic heart disease are administered a dual antiplatelet therapy after percutaneous coronary intervention. This consists of aspirin and thienopyridine, which can be switched from prasugrel to clopidogrel. However, the impact of switching is unknown. This study aimed to determine the efficacy and safety of switching from prasugrel to clopidogrel in Japanese patients. One-hundred and thirty-six patients with acute coronary syndrome scheduled to undergo percutaneous coronary intervention and patients with coronary artery disease requiring elective coronary stenting were enrolled. Patients were randomly assigned into the following groups: prasugrel for 6 weeks at loading/maintenance doses of 20/3.75 mg (Continued Group; n = 68) or prasugrel at 20/3.75 mg for 2 weeks followed by clopidogrel at 75 mg for 4 weeks (Switched Group; n = 68). Aspirin (loading dose/maintenance dose 324/81-100 mg/day) was coadministered in both groups. The primary endpoint was the mean P2Y reaction unit (PRU) at week 6 and the secondary endpoint was the PRU in groups subdivided based on the presence of CYP2C19 gene polymorphisms. At week 6, the PRU was significantly lower in the Continued Group relative to the Switched Group (140.7 and 183.0, respectively; P < 0.001), which was also evident after correction with the baseline values (144.1 vs. 176.6, respectively; P = 0.005). Extensive and poor metabolizers in the Switched Group, based on CYP2C19 gene polymorphisms, had significantly higher PRU values than those in the Continued Group. Thus, switching treatments from prasugrel to clopidogrel significantly increased the PRU in patients receiving antiplatelet therapy subsequent to percutaneous coronary intervention. Clinical Trial Registration UMIN ID, UMIN000015122. [ABSTRACT FROM AUTHOR]

Background Patients with coronary artery disease ( CAD) treated with stents require dual antiplatelet therapy ( DAPT). For cirrhotics, who often have varices and coagulopathy, it is not clear if the risk of gastrointestinal bleeding ( GIB) should preclude use of DAPT. Aim To compare GIB and mortality rates in cirrhotics with CAD treated medically or with stents. Methods Using institutional databases, we identified patients with cirrhosis and CAD treated with stents or medical therapy between January 2000-September 2015. Primary outcomes were GIB and mortality. Results We identified 148 cirrhotics with CAD; 68 received stents (cases), 80 were treated with medical therapy (controls). Cases and controls had similar demographics, comorbidities, MELD scores and clinical presentation; DAPT was used in 98.5% of cases vs 5% of controls. The incidence of GIB was significantly higher in cases than controls (22.1% vs 5% at 1 year, P=.003; 27.9% vs 5% at 2 years, P=.0002), whereas all-cause mortality was similar (20.6% vs 21.3%). No patient required surgery or angiography for GIB, and no known patients died due to GIB. Multivariate analysis revealed use of a proton pump inhibitor ( PPI) was highly protective against GIB ( OR=0.26, 95% CI=0.08-0.79). Conclusions CAD treatment with stents in our cirrhotics was associated with a significantly increased risk of GIB, but no adverse effects on survival. Although it remains unclear whether the cardiovascular benefits of stents outweigh the GIB risk, our findings suggest that DAPT should not be withheld from stented cirrhotics for fear of GIB. Moreover, the use of a PPI should be strongly considered. [ABSTRACT FROM AUTHOR]

The structures, electronic properties, and chemical reactivities of isomeric furo-, thieno- and selenophenopyridines have been studied by B3LYP/6-31G(d) method. The optimized geometries of these isomers show planar configurations. The structural properties such as bond lengths, bond angles, and dipole moments of these isomers were calculated. The energies of frontier molecular orbitals (HOMO and LUMO) are used to determine several chemical reactivity parameters as a measure of their relative stabilities. These include total energy (E), ionization potential (I), electron affinity (A), chemical hardness (η), chemical softness (S), electronic chemical potentials (μ), and electrophilicity (ω). Selepheno[3,4-c]pyridine possesses the highest electrophilicity and minimum chemical hardness among the calculated isomeric structures. The largest calculated dipole moment belongs to furo[2,3-c]pyridine, while thieno[3,2-b]pyridine has the lowest. [ABSTRACT FROM PUBLISHER]

Allergic reactions to clopidogrel soon after coronary stent implantation pose an important and challenging clinical problem. We describe a 44-year-old man who developed a diffuse maculopapular rash four days after initiation of clopidogrel with drug-eluting coronary stent placement. An initial treat-through strategy was unsuccessful due to patient intolerance to corticosteroids. Because of persistent hypersensitivity, clopidogrel was substituted with prasugrel which was continued successfully for one year without reaction. A systematic review of the literature was performed which identified 10 prior case reports of patients with clopidogrel hypersensitivity who were subsequently treated with prasugrel. Patient characteristics and clinical outcomes of these patients plus the current case were reviewed. There were 9 men and 2 women with ages from 44 to 76 years. All patients had undergone coronary stent procedures. Prasugrel was successfully used without cross-reactivity in 9 of the 11 patients (82%). Cross-reactivity was reported in two patients who developed hypersensitivity reactions to prasugrel similar to those experienced on clopidogrel. In conclusion, prasugrel can be used successfully in most patients with a history of clopidogrel hypersensitivity. However, potential cross-reactivity between these two thienopyridines may occur in some patients. [ABSTRACT FROM AUTHOR]