Search

Adding to past success in developing non-nucleoside reverse transcriptase inhibitors (NNRTIs), we report herein our efforts to optimize an FDA-approved NNRTI, doravirine, into a series of novel biphenyl-substituted pyridone derivatives. A strategy focused on harnessing the X-ray crystal structure of doravirine, coupled with computer simulations, to guide the design of conformationally constrained analogs led to the discovery of ZLM-66, which provided comparable inhibitory potency to doravirine against wild-type HIV-1 (EC

Six series of 4-(benzo[c][1,2,5]thiadiazol-5-yl)-3(5)-(6-methylpyridin-2-yl)- pyrazoles 18a–d, 19a–d, 22a–d and 3(5)-(6-methylpyridin-2-yl)-4-(thieno[3,2,-c]- pyridin-2-yl)pyrazoles 20a–d, 21a–d, 23c, 23d have been synthesized and evaluated for their activin receptor-like kinase 5 (ALK5) and p38α mitogen activated protein (MAP) kinase inhibitory activities in enzymatic assays. Among these compounds, the most active compound, 22c, inhibited ALK5 phosphorylation with an IC50 value of 0.030 μM in the enzymatic assay. Compound 22c showed four-fold more potent activity against ALK5 kinase than the clinical candidate, compound LY-2157299. The selectivity index of 22c against p38α MAP kinase is 235, which is much higher than that of LY-2157299 (4) and equally selective to that of EW-7197 (218). Compound 22c effectively suppressed protein and mRNA expression of collagen I and α-SMA in TGF-β-induced LX-2 human hepatic stellate cell (HSC), this result shows that compound 22c has the ability to inhibit the activation of HSC. Compound 22c is expected to be a preclinical candidate for the treatment of hepatic fibrosis.

Several series of novel tryptophan-derived rhodanine derivatives were synthesized and identified as potential competitive PTP1B inhibitors and antibacterial agents. Among the compounds studied, 10b was found to have the best in vitro inhibition activity against PTP1B (IC50 = 0.36 ± 0.02 μM). In addition, the compounds also showed potent inhibition against other PTPs, especially CDC25B. Molecular docking analysis demonstrated that compounds 7c and 10b could occupy both the catalytic site and the adjacent pTyr binding site simultaneously. The compounds also showed higher levels of activity against gram-positive strains, the gram-negative strain Escherichia coli 1924, and multidrug-resistant gram-positive bacterial strains. Compounds 7c, 8c, 9e, 10a, and 10c had comparable or more potent antibacterial activity than the positive controls.

Drugs of targeting both activin receptor-like kinase 5 (ALK5) and p38α have therapeutic advantages, making them attractive treatment options for tumors. Two series of 4-(1H-indazol-5-yl)-5-(6-methylpyridin-2-yl)-1H-imidazoles 13a–g and 4-(1-methyl-1H-indazol-5-yl)-5-(6-methylpyridin-2-yl)-1H-imidazoles 20a–g were synthesized and evaluated for ALK5 and p38α mitogen-activated protein kinase inhibitory activity. The most potent compound, 13c (J-1090), inhibited ALK5- and p38α-mediated phosphorylation with half-maximal inhibitor concentrations of 0.004 μM and 0.004 μM, respectively, in the enzymatic assay. In this study, the effectiveness of 13c in transforming growth factor (TGF-β)-exposed U87MG cells was investigated using western blotting, immunofluorescence assays, cell migration assay, invasion assay, and RT-PCR analysis. 13c inhibited the protein expression of Slug and the protein and RNA expression of the mesenchymal-related proteins N-cadherin and vimentin. Furthermore, 13c markedly suppressed TGF-β-induced epithelial-to-mesenchymal transition (EMT), migration, and invasion in U87MG cells. These results suggest that 13c is a novel inhibitor of ALK5 with potential utility in the treatment of human glioma.

A series of novel naphthyl-diarylpyrimidine (DAPY) derivatives were designed and synthesized to explore the entrance channel of the non-nucleoside reverse transcriptase inhibitors binding pocket (NNIBP) by incorporating different flexible side chains at the C-6 position. The biological evaluation results showed that all analogues possessed promising HIV-1 inhibitory activity at the nanomolar concentration range. Three compounds (7, 9 and 39) displayed excellent potency against WT HIV-1 strain with EC50 values ranging from 5 to 10 nM and high selectivity indexes (SI = 3504, 30488 and 22846, respectively), which were higher than for nevirapine and comparable to the values for etravirine. The RT inhibition activity, preliminary structure-activity relationship and molecular docking study showed that the side chain at the C-6 position of the DAPYs occupied the entrance channel and significantly influenced anti-HIV activity and selectivity. Additionally, the physicochemical properties were investigated to evaluate the drug-like features, which indicated that introducing various substituents on the pyrimidine ring can improve solubility.

Two novel series of 3-((5-phenyl-1,3,4-oxadiazol-2-yl)methyl)-2-thioxothiazolidin-4-one derivatives were designed and synthesized, and their anti-bacterial activities evaluated. These compounds showed broad-spectrum inhibitory activities against both Gram-positive and Gram-negative bacteria with minimum inhibitory concentration (MIC) values in the range of 1–64 μg/mL. The activity of compound 6c was the more potent with MIC values of 1 μg/mL against the MRSA (3167 and 3506) strains than those of gatifloxacin, oxacillin, and norfloxacin. Compared to the previously reported rhodanine derivatives, 2-thioxothiazolidin-4-one derivatives exhibited an inhibition against Gram-negative strains due to the introduction of a 1,3,4-oxadiazole moiety, among which compounds 3 showed moderate activities against the Gram-negative bacteria (Escherichiacoli 1924) with MIC values of 16 μg/mL.

A series of novel nonphosphonate-based pTyr mimetics comprised (±)-3-(2-(2-fluorobenzyloxy)naphthalen-6-yl)-2-aminopropanoic acid derivatives were identified as reversible and competitive PTP1B inhibitors via a structure-based design approach. Among the compounds studied, 12h was found to have the best in vitro inhibition activity against PTP1B (IC(50) = 1.25 ± 0.24 μM) and the best selectivity (3-fold) between PTP1B and TCPTP. These results should provide suitable druglike lead compounds for the design of inhibitors of PTP1B as well as other PTPs.

A series of chalcone derivatives bearing the 2,4-thiazolidinedione and benzoic acid moieties ( 8a – s ) were synthesized, characterized, and evaluated for their anti-bacterial activity. Among the tested compounds, the most effective were 8a , 8h , 8k , 8n and 8q with MIC value in the range of 0.5–4 μg/mL against six Gram-positive bacteria (including multidrug-resistant clinical isolates). None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 and E. coli 1682 at 64 μg/mL.

With an intention to synergize the anti-bacterial activity of chalcones and rhodanine-3-acetic acid, several hybrid compounds possessing chalcone and rhodanine-3-acetic acid moieties were synthesized and tested for their anti-bacterial activity. Some compounds presented great anti-microbial activities against Gram-positive bacteria (including the multidrug-resistant clinical isolates). This class of compounds presented high potency against Staphylococcus aureus, among which the derivatives 5k with a MIC of 2 μg/mL was as active as the standard drug (norfloxacin) and less active than oxacillin. Compounds 5a-s did not inhibit the growth of Gram-negative bacteria Escherichia coli CCARM 1924 or E. coli CCARM 1356 at 64 μg/mL.

A series of 7-benzylamino-2 H -1,4-benzoxazin-3(4 H )-ones were synthesized using 2-amino-5-nitrophenol as a starting material. Their anticonvulsant activities were evaluated by the maximal electroshock test (MES test) and their neurotoxicity was evaluated by the rotarod neurotoxicity test (Tox.). The MES test showed that 7-(4-fluorobenzylamino)-2 H -1,4-benzoxazin-3(4 H )-one 4b was the most potent with ED 50 value of 31.7 mg/kg and protective index (PI = TD 50 /ED 50 ) value of 7.2. To explain the possible mechanism of anticonvulsant activity, the compound 4b was tested in sc-PTZ test, isoniazid test and strychnine test.

With an intention to synergize the anti-bacterial activity of 5-aryloxy pyrazole and rhodanine derivatives, eight series of hybrid compounds have been synthesized and evaluated for their antibacterial activity. The majority of the synthesized compounds showed good inhibitory activity against selected methicillin resistant and quinolone-resistant Staphylococcus aureus (MRSA, QRSA) with minimum inhibitory concentration (MIC) values in the range of 1-32 μg/mL. The cytotoxicity test suggests that these compounds exhibited in vitro antibacterial activity at non-cytotoxic concentrations. These studies therefore suggest that rhodanine-based 5-aryloxy pyrazoles are interesting scaffolds for the development of novel Gram-positive antibacterial agents.

Four novel series of compounds, including the l -phenylalanine-derived C5-substituted rhodanine (6a–q, 7a–j) and chalcone derivatives containing thiobarbituric acid or 2-thioxo-4-thiazolidinone (9a–e, 11a–e) have been designed, synthesized, characterized, and evaluated for their antibacterial activity. Some of these compounds showed significant antibacterial activity against Gram-positive bacterias, especially against the strains of multidrug-resistant clinical isolates, among which compounds 6c–e, 6g, 6i, 6j and 6q exhibiting high levels of antimicrobial activity against Staphylococcus aureus RN4220 with minimum inhibitory concentration (MIC) values of 2 μg/mL. Compound 6q showed the most potent activity of all of the compounds against all of the test multidrug-resistant clinical isolates tested. Unfortunately, however, none of the compounds were active against Gram-negative bacteria at 64 μg/mL.

In the present study, a series of novel 1,3-diphenyl-1 H -pyrazoles functionalized with phenylalanine-derived rhodanine derivatives were synthesized and evaluated for their antibacterial activity. Compounds 4 , 6 , 9 , 10 , 12 and 15 exhibited stronger activity than the standard drugs, norfloxacin and oxacillin, with MIC values of 1 μg/mL against methicillin-resistant Staphylococcus aureus and quinolone-resistant S. aureus . None of the compounds showed any activity against Gram-negative bacteria.

Five series of ( Z )-5-(4-(2-oxo-2-phenylethoxy)benzylidene)-2-thioxothiazolidin-4-one derivatives ( I–V ) were synthesized, characterized, and evaluated for their anti-bacterial activity. Most of the synthesized compounds showed potent inhibition against several Gram-positive bacteria (including multidrug-resistant clinical isolates) with MIC values in the range of 1–32 μg/mL. Compounds IIIi , Vb and Vc presented the most potent activity, showing four-fold more potency than norfloxacin (MIC = 8 μg/mL and 4 μg/mL) and 64-fold more activity than oxacillin (MIC > 64 μg/mL) against MRSA CCARM 3167 and 3506 strains with MIC values of 1 μg/mL, and 64-fold more potency than norfloxacin (MIC > 64 μg/mL) and comparable activity to oxacillin (MIC = 1 μg/mL) against the QRSA CCARM 3505 and 3519 strains. None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 at 64 μg/mL.

30 novel compounds have been synthesized from 25-hydroxyprotopanaxadiol (25-OH–PPD) and their in vitro anti-tumor activities were tested on three cancer cell lines and one normal cell line (IOSE144) by standard MTT assay. The results showed that compound 27 exhibited the best anti-tumor activity in the in vitro assays. Compounds 1 , 2 , 16 , 17 , 18 , 27 , 28 and 29 have better anti-tumor activities against MCF-7 and A549 cancer cell lines than 25–OH–PPD, together with low toxicity in the normal cell. The results may provide useful data for researching and developing new antitumor agents.

In the present study, a series of 1,3-diaryl pyrazole derivatives bearing rhodanine-3-fatty acid moieties were synthesized and their antimicrobial activities were tested against various Gram-positive and Gram-negative bacteria. 1,3-diaryl-4-formylpyrazoles were synthesized as key intermediates following a Vilsmeier–Haack strategy. Several compounds with an MIC of 2 μg/mL, exhibited stronger antibacterial activity against the methicillin-resistant Staphylococcus aureus (MRSA) than the controls. None of the compounds showed any activity against Gram-negative bacteria.

A series of novel N-(2-hydroxyethyl) cinnamamide derivatives were synthesized and screened for their anticonvulsant activities by the maximal electroshock (MES) test and their neurotoxicity was evaluated by the rotarod neurotoxicity test (Tox). The MES test showed that compounds I(N-(2-hydroxyethyl) cinnamamide) and 1d ((E)-3-(3-fluorophenyl)-N-(2-hydroxyethyl)acrylamide) were found to possess better anticonvulsant activity but also had lower toxicity. In the anti-MES potency test, these compounds exhibited median effective dose (ED(50)) of 17.7 and 17.0 mg/kg, respectively, and median toxicity dose (TD(50)) of 154.9 and 211.1, respectively, resulting in a protective index (PI) of 8.8 and 12.4, respectively, which is much greater than the PI of the marked antiepileptic drug carbamazepine. To further investigate the effects of the anticonvulsant activity in several different models, compounds I and 1d were tested against convulsions induced by chemical substances, including pentylenetetrazole (PTZ), isoniazid, 3-mercaptopropionic acid, and thiosemicarbazide.

In an attempt to search for more potent positive inotropic agents, a series of 2-(4-substitutedmethylpiperazin-1-yl)- N -(3,4-dihydro-3-oxo-2 H -benzo[ b ][1,4]oxazin-7-yl)acetamides were synthesized and their positive inotropic activities were evaluated by measuring left atrium stroke volume on isolated rabbit heart preparations. Several compounds showed favorable activities compared with the standard drug, milrinone, among which 2-(4-(4-methylbenzyl)piperazin-1-yl)- N -(3,4-dihydro-3-oxo-2 H -benzo[ b ][1,4]oxazin-7-yl)acetamide 4e showed the most potent activity with the 5.09 ± 0.00% increased stroke volume (milrinone 1.67 ± 0.64%) at a concentration of 1 × 10 −5 M in our in vitro study. The chronotropic effects of those compounds having significant inotropic effects were also evaluated in this work.

A new series of 8-alkoxy-5,6-dihydro-[1,2,4]triazino[4,3- a ]quinolin-1-one derivatives were synthesized. Their anticonvulsant activities were evaluated by the maximal electroshock (MES) test, and their neurotoxicities were evaluated by the rotarod neurotoxicity test. The results showed that 8-heptyloxy-5,6-dihydro-[1,2,4]triazino[4,3- a ]quinolin-1-one 5t was the most potent with median effective dose (ED 50 ) value of 11.4 mg/kg, median toxicity dose (TD 50 ) of 114.1 mg/kg, providing a protective index (PI = TD 50 /ED 50 ) value of 10.0, which is much greater than the PI of the prototype drug carbamazepine (PI = 6.4). To explain the possible mechanism of anticonvulsant activity, the compound 5t was tested in chemically induced seizures.