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Patient Initials or Identifier Number YKV ### Relevant Clinical History and Physical Exam A 50-year-old gentleman with hypertension presented initially in February 2018 for inferior MI, was successfully thrombolysed and coronary angiogram done a few days later only showed a mild coronary

Discovery of a novel nor-seco himbacine analog as potent thrombin receptor (PAR-1) antagonist is described. Despite low plasma level, these new analogs showed excellent ex vivo efficacy in the monkey platelet aggregation assay. A potent hydroxy metabolite generated in vivo was identified as the agent responsible for the ex vivo efficacy. Following this discovery, the metabolite series was optimized to obtain analogs that showed very good ex vivo efficacy along with excellent pharmacokinetic profile in c. monkey.

A series of pyrazoloquinoline analogs have been synthesized and shown to bind to PDE10 with high affinity. From the SAR study and our lead optimization efforts, compounds 16 and 27 were found to possess potent oral antipsychotic activity in the MK-801 induced hyperactive rat model.

Use of liquid chromatography/tandem mass spectrometric (LC/MS(n)) molecular fingerprinting is systematically demonstrated as a very effective tool for rapid structural elucidation of pharmaceutical impurities through a case study in which three isomers of betamethasone sodium phosphate (BSP) were rapidly identified as degradants formed due to the D-homoannular ring expansion of the steroid core structure of BSP in the solid state. The rapid structural elucidation of these degradants was achieved by matching or closely matching the UV profiles, molecular weights, and more importantly the fragmentation patterns obtained from the LC/MS(n) (n = 1 to 3) analysis of their enzyme-catalyzed hydrolytic products, respectively, with those of a D-homoannular isomer of betamethasone available in our LC/MS(n) molecular fingerprint database. This strategy of using LC/MS(n) molecular fingerprinting to obtain high-confidence structures of unknown species is then validated by structure verification through one- (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) experiments.

Investigation of unexpected levels of impurities in Intron product has revealed the presence of low levels of impurities leached from the silicone tubing (Rehau RAU-SIK) on the Bosch filling line. In order to investigate the effect of these compounds (1a, 1b and 2) on humans, they were isolated identified and synthesized. They were extracted from the tubing by stirring in Intron placebo at room temperature for 72 h and were enriched on a reverse phase CHP-20P column, eluting with gradient aqueous ACN and were separated by HPLC. Structural elucidation of 1a, 1b and 2 by MS and NMR studies demonstrated them to be halogenated biphenyl carboxylic acids. The structures were confirmed by independent synthesis. Levels of extractable impurities in first filled vials of actual production are estimated to be in the range of 0.01-0.55 microg/vial for each leached impurity. Potential toxicity of these extractables does not represent a risk for patients under the conditions of clinical use.

This report describes a novel regioselective contra-Michael addition to cinnamic esters that utilizes NaNO 2 –ceric ammonium nitrate.

A variation of the Mattox rearrangement, a key degradation pathway under acidic conditions for corticosteroids possessing the 1,3-dihydroxyacetone side chain, has been found to occur for the 17,21-diesters of these corticosteroids but under the alkaline condition. The mechanism of this variation of the original Mattox rearrangement is proposed.

Versatile syntheses of dipeptides that incorporate the 3-azabicyclo[3.1.0]hexane system are described.

The structure–activity relationship (SAR) of the lactone ring of himbacine derived thrombin receptor (PAR-1) antagoinsts (e.g., 2 – 5 ) is described. The effect of the lactone carbonyl group on binding to PAR-1 is dependent on the substitution pattern of the pyridine ring. A stereoselective intramolecular Michael addition reaction to the vinyl pyridine group was observed for these pyridine analogs of himbacine in basic conditions at elevated temperature.

An efficient and practical synthesis of sterically hindered N-substituted lactams has been developed starting from simple starting materials. The stereochemistry of the synthetically useful N,N acetal intermediate has been established.

Two novel chemokine receptor CCR-5 inhibitors, Sch 210971 (1) and Sch 210972 (2), were isolated from the fungal fermentation broth of Chaetomium globosum by normal- and reversed-phase HPLC purifications. The structure determination of 1 and 2 was accomplished on the basis of UV, MS, and NMR spectral data analyses including COSY, NOESY, HMQC, and HMBC experiments. The structure and relative configuration of 2 were determined unequivocally by X-ray crystallographic analysis. The major component 2 demonstrated a potent inhibitory activity of IC(50) = 79 nM in the CCR-5 receptor in vitro binding assay.

Macrocyclization through a Mitsunobu reaction was used to synthesize a 17-membered macrocycle. The bicyclic acetal core was prepared completely diastereoselectively. The macrocyclic peptidomimetic surrogate of the P2-P3 dipeptide moiety was designed to function as a hepatitis C virus (HCV) NS3 serine protease inhibitor, and the pentapeptide {alpha}-ketoamides derived from the macrocycle were shown to be potent HCV inhibitors.

Using radical chemistry novel highly condensed heterocycles have been synthesized. The mechanism for their formation is discussed.

Two new secondary metabolites designated as Sch 419558 ( 1 ) and Sch 419559 ( 2 ), were isolated from the fermentation broth of Pseudomonas fluorescens . Structure elucidation of 1 and 2 was accomplished by spectroscopic data analyses including MS and NMR experiments. Both compounds were identified as lipopeptides containing valine and threonine linked with 1-amino-1-hydroxy-heptadec-9-en-2-one or 1-amino-1-hydroxy-pentadecan-2-one carbon chains, respectively. Characterization of the amino acids was further confirmed by amino acid analysis. Compounds 1 and 2 exhibited antibacterial activity against a sensitized E. coli strain with minimum inhibitory concentration of 0.3 and 0.6 μg/mL, respectively. Overexpression of RpoE in the E. coli strain increased the MIC over 60-fold for compounds 1 and 2 .

Synthesis of novel heterocycles using radical reactions have been described. Reaction mechanism of their formation is also presented.

A convenient synthesis of novel 2,2,4-trisubstituted pyrrolidines via stereoselective 5-exo iodocyclization of the 2,2-disubstituted olefins 8 and 9 is described. Single crystal X-ray analysis of the oxazolidinone 15 confirmed the relative stereochemistry in this cyclization. As observed earlier in the formation of 2,2,4-trisubstituted tetrahydrofurans, the presence of a bulky aryl substituent on the olefin appears to direct the stereochemical outcome of these halocyclizations.

Two novel antibiotics, Sch 484129 (1) and Sch 484130 (2), were isolated from the fermentation broth of a fungal culture, which was identified as a Basidiomycete. The new antibiotics were obtained by ethyl acetate extraction followed by reversed phase HPLC purification. Structure elucidation of 1 and 2 was accomplished by spectroscopic data analyses. Derivatizations of the major component 1 were performed in order to provide definitive structural information. Both components were identified as glycolipids and displayed antifungal activity against Saccharomyces and Aspergillus strains.

A simple isocratic reversed-phase high performance liquid chromatograghic method for the separation of pseudoephedrine and its related compounds in pharmaceutical formulations is described. The separation is achieved in less than 35 min on a C-18 column (4.6 mm I.D. x 25 cm length, 5-micrometer particle size) using a mobile phase consisting of a mixture of ammonium acetate and methanol. The results described in this report demonstrate that the method is sensitive and selective. Structural elucidation of two new pseudoephedrine degradation products is described. On the basis of structural analysis by liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-nuclear magnetic resonance spectroscopy (LC-NMR), the two newly elucidated degradation products were identified to be 2-(carboxyamino)propiophenone (molecular ion of m/z=194) and 2-formyl-2-(methylamino)-acetophenone (molecular ion of m/z=178).

A generalised radical reaction has been used to synthesise heterocyclic compounds which could serve as ligands for drug discovery. Attempt also have been made to rationalise the formation of oxidation products formed during TBTH reaction.

Two new C-nor/D-homo corticosteroids were isolated from the filtrate of the triene carbonate intermediate during the production of betamethasone. Their structures were elucidated based on NMR spectroscopic studies and mass spectral analyses. The mechanism of formation of each of these two steroids was postulated as a Wagner-Meerwein rearrangement of the corresponding 12beta-hydroxy steroid. The new 12beta-hydroxy corticosteroid was also isolated from the fermentation process of betamethasone synthesis. Its structure was identified via NMR and mass spectroscopic studies. Treatment of the new 12beta-hydroxy corticoid with PCl(5) at low temperature provided two C-nor/D-homo compounds in a ratio of 1:1. Conversion of 12beta-hydroxy corticoid into a corresponding 12beta-mesylate followed by heating in HOAc to 110 degrees C in the presence of NaOAc produced a mixture of the rearranged products in a 1:4 ratio.

Starting from N-Cbz-4-hydroxyproline methyl ester 1, a boron trifluoride-diethyl etherate-catalyzed reaction provided 4-tert-alkyl ether proline 4. Two deprotections and amide bond formations furnished the phenol alcohol 2. The macrocyclization of 2 was accomplished through a Mitsunobu reaction using triphenylphosphine and 1,1'-(azodicarbonyl)dipiperidine (ADDP), to afford novel 16- and 17-membered proline-based macrocyclic compounds of type 3.

A general synthetic approach to 4,6-substituted thiazole[4,5-c]pyridines, involving a novel one-pot thiol deprotection-cyclization key step, is described.

The first enantioselective syntheses of carbocyclic ribavirin by both convergent and linear approaches are described. The linear approach from chiral nonracemic 2-azabicyclo[2.2.1]hept-5-en-3-one proves to be a highly efficient route to carbocyclic analogs of ribavirin.

A novel oligosaccharide, Sch 58761 ( 1 ), was isolated from the fermentation broth of Micromonospora carbonaceae using diol-bonded/polyvinyl alcohol-functionalized silica gel (PVA-Sil) purification. Structure determination of 1 was accomplished by extensive mass spectrometric and NMR studies.

A mechanistic study of the simple sequential N-arylation of piperazine suggests that in an electron-withdrawing group (EWG) containing N-arylated piperazines, hydrogen bonding of the secondary amine hydrogen is important for its non-metal catalyzed conversion to N,N′-diaryl piperazines. A combination of synthetic experiments, molecular modeling, and NMR studies were carried out to test this hypothesis.

Chemical modifications of eveminomicin antibiotics, particularly ziracin (1), were carried out to study the SARs as well as the chemical properties of this class of compounds. Use of allyl ether group for protection and selective deprotection of phenolic groups provided access to a variety of novel analogs of the title compounds, some of which exhibited the same high in vitro potency as the parent compounds.

The tandem Pauson-Khand reaction has been extended to the synthesis of [5.6.6.5]dicyclopenta[ b,g ]decalins. This approach provides a unique entry into a cis -fused decalin-based ring system via an acyclic precursor.

Degradation of Sch 49088 (1) provided a novel, highly functionalized O-substituted hydroxylamine-containing sugar, everhydroxylaminose 11 isolated as a β-OMe glycoside. Notably the two acid sensitive orthoester moieties in the intact antibiotic 1 co-exist in the presence of three phenolic groups and a free carboxylic acid group.

The metabolism of SCH 40120, which is the clinically effective antipsoriatic drug 10-(3-chlorophenyl)-6,8,9,10-tetrahydrobenzol[b][1,8]naphthyrid in-5(7H)-one, was determined in vitro. Rat, dog, cynomolgus monkey, and human liver slices hydroxylated the aliphatic, cyclohexenyl ring of the drug and conjugated the resulting carbinol. The identified metabolites comprised the corresponding 6-, 7-, and 9-carbinols, the glucuronide of the 6-carbinol, and the 6-ketone derived from the parent drug. Although the three carbinols appeared in the liver isolates of all species studied, the relative amounts of these metabolites varied across species. With a high, non-physiological ratio of substrate to liver, the 6-carbinol and its glucuronide were the major metabolites in human and monkey, whereas the 6-ketone was a minor metabolite in dog. Containing a stereogenic axis and center, the 6-carbinol existed as diastereomeric atropisomers. Its structure was established by 13C and 1H NMR spectroscopy, mass spectrometry, and comparison to an authentic sample.

A comprehensive study of nitration reaction of azatricyclic systems has been carried out. Whereas classical nitrations using KNO(3)-H(2)SO(4) at low temperatures gave nitrated products mainly at the 9-position, use of tetrabutylammonium nitrate-trifluoroacetic anhydride (TBAN-TFAA) resulted in exclusive nitration of the 3-position in the case carbamates 1, and 4-6 and the tricyclic ketone 7. These 3-nitro tricyclic derivatives have been valuable intermediates for the preparation of the very potent farnesyl protein transferase inhibitors such as the tricyclic pyridyl acetamide 32 and other new analogues.

A new 5-alkenylresorcinol Sch725681 (1) was isolated and identified from the culture of an Aspergillus sp. The structure elucidation of 1 was accomplished based on extensive NMR spectroscopic analyses. Compound 1 showed inhibitory activity against Saccharomyces cerevisiae (PM503) and Candida albicans (C43) with MICs of 16 and 64 microg/ml, respectively.

The absolute stereochemistry at C16 orthoester center of Ziracin ( 1 ) was unequivocally established via a novel acid-catalyzed orthoester isomerization. Structures of the resulting isomers 2 and 3 were determined by chemical degradation and extensive spectroscopic analyses. This novel isomerization was successfully extended to other related everninomicins ( 11–13 ), thus completing the entire structural assignment of everninomicin antibiotics. © 1997 Elsevier Science Ltd.

A technique for reliably selecting a transmitter position for rotating-frame NOE experiments which minimize scalar coupling artifacts is described. The technique makes use of the COSY spectrum of the molecule in question. The method is illustrated by application to thiostrepton, an antibiotic of molecular weight 1665. For an individual compound, the range of transmitter settings over which HOHAHA distortions are observed is found to depend on the molecular correlation time of the compound under study. The origin of this effect is discussed in terms of rotating-frame relaxation during the spin-lock period.

The 70% aqueous methanolic extract of the Peruvian plant Oryctanthus sp. was found to contain a novel saccharide of a diene alpha,omega-diacid. Compound 1 was identified as an inhibitor of the VEGF receptor. The structure of this compound was established based on NMR studies. Compound 1 inhibited ligand binding to the VEGF receptor with an IC50 of 5.0 microM.

Two isomers of betamethasone 9α-fluoro-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione (1), were isolated from the mother liquor of a manufacturing process and were characterized by NMR spectroscopy. They were identified as 8α-fluoro-11β,17α,21-trihydroxy-16β-methyl-9β-pregna-1,4-diene-3,20-dione (2) and 14β-fluoro-11β,17α,21-trihydroxy-16β-methyl-8α,9β-pregna-1,4-diene-3,20-dione (3). The stereochemistries of 2 and 3 were assigned on the basis of proton–proton and proton–fluorine NOE experiments. The structure of the former was confirmed by x-ray crystallographic analysis.

A novel hepatitis C virus (HCV) proteinase inhibitor, Sch 68631 ( 1 ), was isolated from the fermentation culture broth of Streptomyces sp. The structure of 1 was elucidated by analyses of spectroscopic data and shown to be a new member of the phenanthrenequinone family of compounds.

Three condensed aromatic peptides SCH79235 ( 1 ), SCH79236 ( 2 ), and SCH204698 ( 3 ) were isolated from the fermentation broth of a Streptomycete microorganism. The structure of SCH204698 ( 3 ) was established by extensive NMR spectral data. All these compounds exhibited good activity against CD28–CD80 binding with an IC 50 of 0.42, 0.38 and 0.22 μM, respectively.