Month: November 2022

Thakur, Nimisha published the artcileEnantiomeric impurities in chiral catalysts, auxiliaries, and synthons used in enantioselective syntheses. Part 5, Application In Synthesis of 171877-39-7, the main research area is chiral catalyst synthon enantioselective enantiomeric impurity; chiral separation; enantiomeric excess; enantiomeric impurity; enantioselective syntheses.

The enantiomeric excess of chiral starting materials is one of the important factors determining the enantiopurity of products in asym. synthesis. Fifty-one com. available chiral reagents used as building blocks, catalysts, and auxiliaries in various enantioselective syntheses were assayed for their enantiomeric purity. The test results were classified within five impurities level (ie, <0.01%, 0.01%-0.1%, 0.1%-1%, 1%-10%, >10%). Previously from 1998 to 2013, several reports have been published on the enantiomeric composition of more than 300 chiral reagents. This series of papers is necessitated by the fact that new reagents are forthcoming and that the enantiomeric purity of the same reagent can vary from batch to batch and/or from supplier to supplier. This report presents chiral liquid chromatog. (LC) and gas composition(GC) methods to sep. enantiomers of chiral compounds and evaluate their enantiomeric purities. The accurate and efficient LC anal. was done using newly introduced superficially porous particle (SPP 2.7μm) based chiral stationary phases (TeicoShell, VancoShell, LarihcShell-P, and NicoShell).

Chirality published new progress about Enantioselective synthesis. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Application In Synthesis of 171877-39-7.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Robichaud, Joeel published the artcileA Novel Class of Nonpeptidic Biaryl Inhibitors of Human Cathepsin K, Name: 2-(2-Phenylthiazol-4-yl)acetic acid, the main research area is nonpeptidic biaryl compound preparation cathepsin K inhibitor.

A novel series of nonpeptidic biaryl compounds was identified as potent and reversible inhibitors of cathepsin K. The P2-P3 amide bond of a known amino acetonitrile dipeptide was replaced with a Ph ring, thereby giving rise to this biaryl series that retained potency vs. cathepsin K and showed an improved selectivity profile against other cathepsins. Structural modification within this series resulted in the identification of compound (R)-2, a potent human cathepsin K inhibitor (IC50 = 3 nM) that is selective vs. cathepsins B (IC50 = 3950 nM), L (IC50 = 3725 nM), and S (IC50 = 2010 nM). In an in vitro assay involving rabbit osteoclasts and bovine bone, compound (R)-2 inhibited bone resorption with an IC50 of 95 nM. It was shown that, unlike some peptidic nitrile inhibitors of cysteine proteases, the nitrile moiety of (R)-2 is not converted to the corresponding amide 3 by cathepsin K. This indicates that this class of nonpeptidic nitrile inhibitors is unlikely to be hydrolyzed by cysteine proteases. Furthermore, the inhibition of cathepsin K by compound (R)-2 was shown to be fully reversible and not observably time-dependent. To demonstrate the efficacy of compound (R)-2 in vivo, it was administered to ovariectomized (OVX) rhesus monkeys at 20 mg/kg, p.o. once daily for 8 days, and a urinary marker of bone turnover, N-telopeptide of type I collagen (uNTx), was measured. During the eight-day dosing period, the mean reduction by compound (R)-2 in uNTx was 80%. This demonstrates that inhibition of cathepsin K leads to an inhibition of this bone resorption marker in OVX rhesus monkeys and strongly suggests that inhibition of cathepsin K is a viable therapeutic approach for the treatment of osteoporosis.

Journal of Medicinal Chemistry published new progress about Bone resorption inhibitors. 16441-28-4 belongs to class thiazole, name is 2-(2-Phenylthiazol-4-yl)acetic acid, and the molecular formula is C11H9NO2S, Name: 2-(2-Phenylthiazol-4-yl)acetic acid.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Huang, Gaochao published the artcileEnantioselective Synthesis of Dilignol Model Compounds and Their Stereodiscrimination Study with a Dye-Decolorizing Peroxidase, COA of Formula: C10H11NS2, the main research area is dilignol model compound enantioselective preparation surface plasmon resonance TcDyP.

A four-step enantioselective approach was developed to synthesize anti (1R,2S)-I and (1S,2R)-I containing a β-O-4 linkage in good yields. A significant difference was observed for the apparent binding affinities of four stereospecific lignin model compounds with TcDyP by surface plasmon resonance, which was not translated into a significant difference in enzyme activities. The discrepancy may be attributed to the conformational change involving a loop widely present in DyPs upon H2O2 binding.

Organic Letters published new progress about Diastereoselective synthesis. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, COA of Formula: C10H11NS2.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Royo, Santiago published the artcileDipeptidyl Enoates As Potent Rhodesain Inhibitors That Display a Dual Mode of Action, Safety of (S)-4-Benzylthiazolidine-2-thione, the main research area is dipeptidyl enoate derivative preparation rhodesain inhibitor trypanosomicides; dipeptidyl enoates; inhibitors; rhodesain; sleeping sickness; trypanosomiasis.

Dipeptidyl enoates were prepared through a high-yielding two-step synthetic route. They have a dipeptidic structure with a 4-oxoenoate moiety as a warhead with multiple reactive sites. Dipeptidyl enoates were screened against rhodesain and human cathepsins B and L, and were found to be potent and selective inhibitors of rhodesain. Among them (S,E)-Et 5-((S)-2-{[(benzyloxy)carbonyl]amino}-3-phenylpropanamido)-7-methyl-4-oxooct-2-enoate (6) was the most potent, with an IC50 value of 16.4 nΜ and kinact/Ki=1.6×106 Μ-1 s-1 against rhodesain. These dipeptidyl enoates display a reversible mode of inhibition at very low concentrations and an irreversible mode at higher concentrations Inhibition kinetics data, supported by docking studies, suggest a dual mode of action via attack of cysteine thiolate at two reactive positions.

ChemMedChem published new progress about Enzyme inhibitors (rhodesain). 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Safety of (S)-4-Benzylthiazolidine-2-thione.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Yu, Wensheng published the artcileDiscovery of MK-6169, a Potent Pan-Genotype Hepatitis C Virus NS5A Inhibitor with Optimized Activity against Common Resistance-Associated Substitutions, Recommanded Product: 2-Ethylthiazole-5-carbaldehyde, the main research area is imidazolylbenzooxazinoindole preparation MK6169 antiviral hepatitis C virus NS5A inhibitor.

We describe the discovery of MK-6169 (I), a potent and pan-genotype hepatitis C virus NS5A inhibitor with optimized activity against common resistance-associated substitutions. SAR studies around the combination of changes to both the valine and aminal carbon region of elbasvir led to the discovery of a series of compounds with substantially improved potency against common resistance-associated substitutions in the major genotypes, as well as good pharmacokinetics in both rat and dog. Through further optimization of key leads from this effort, MK-6169 (I) was discovered as a preclin. candidate for further development.

Journal of Medicinal Chemistry published new progress about Anti-hepatitis C virus agents. 933683-87-5 belongs to class thiazole, name is 2-Ethylthiazole-5-carbaldehyde, and the molecular formula is C6H7NOS, Recommanded Product: 2-Ethylthiazole-5-carbaldehyde.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Tungen, Joern E. published the artcileStereoselective synthesis of maresin 1, Name: (S)-4-Benzylthiazolidine-2-thione, the main research area is maresin 1 stereoselective preparation diastereoselective Evans Nagao aldol.

Maresin 1 (I) is a potent anti-inflammatory and pro-resolving lipid mediator derived from docosahexaenoic acid. The total synthesis of maresin 1 is achieved in 10 steps and in 7% overall yield. The Evans-Nagao aldol reaction between (2E,4E)-5-bromopenta-2,4-dienal and different chiral auxiliaries is investigated. The reported synthesis is efficient and highly stereoselective, affording multi-milligram quantities of this biol. interesting lipid mediator.

Tetrahedron Letters published new progress about Aldol addition, stereoselective. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Name: (S)-4-Benzylthiazolidine-2-thione.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Skaanderup, Philip R. published the artcileSynthesis of the Macrocyclic Core of (-)-Pladienolide B, Formula: C10H11NS2, the main research area is pladienolide B macrocyclic core stereoselective preparation.

An efficient synthesis of the macrocyclic core (I) of (-)-pladienolide B is disclosed. The concise route relies on a chiral auxiliary-mediated asym. aldol addition and an osmium-catalyzed asym. dihydroxylation to install the three oxygenated stereocenters of the macrocycle. This purely reagent-controlled and flexible strategy sets the stage for future analog syntheses and structure-activity relationship plotting of the appealing anticancer lead structure pladienolide B.

Organic Letters published new progress about Aldol addition, stereoselective. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Formula: C10H11NS2.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Raghavan, Sadagopan published the artcileA Stereoselective Synthesis of the Carbon Backbone of Phoslactomycin B, Application In Synthesis of 171877-39-7, the main research area is stereoselective synthesis carbon backbone phoslactomycin B; propargylic sulfide rearrangement unsaturated ketone phoslactomycin B synthesis; aldol stereoselective phoslactomycin B synthesis; asym transfer hydrogenation phoslactomycin B synthesis; diyne partial reduction phoslactomycin B synthesis.

A convergent synthesis of the entire carbon framework of phoslactomycin B (I) is disclosed. An initial route aimed to create the C-8 tetrasubstituted stereocenter through regioselective intermol. coupling between an internal alkyne and an allyl silyl ether, adopting Trost’s protocol, followed by [2,3] sigmatropic rearrangement. But this was not successful. In a second approach, a propargylic sulfide was rearranged to give an unsaturated ketone. This was then treated with lithio acetonitrile to create the C-8 stereocenter selectively. The C-4 and C-5 stereocenters were introduced by a non-Evans syn-aldol reaction using Crimmins’s protocol. The C-9 and C-11 carbinol centers were created by asym. transfer hydrogenation. The (Z,Z)-diene moiety was introduced by partial reduction of a diyne following Hansen’s modification of the Boland reduction reaction.

European Journal of Organic Chemistry published new progress about Aldol addition, stereoselective. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Application In Synthesis of 171877-39-7.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Sunnapu, Ranganayakulu published the artcileStereoselective Total Synthesis of (-)-(2S,4R)-3′-Methoxyl Citreochlorol: Preparation and Use of New Proline-Based Auxiliary for Asymmetric Acetate Aldol Reaction, HPLC of Formula: 171877-39-7, the main research area is methoxyl citreochlorol stereoselective total synthesis asym aldol.

The first stereoselective total synthesis of (-)-(2S,4R)-3′-methoxy citreochlorol and (+)-(2S,4S)-3′-methoxy citreochlorol, I (R = OH, R1 = H; R = H, R1 = OH, resp.) is demonstrated. A proline-based imidazolidinone, II, was synthesized and used as chiral auxiliary for the asym. acetate aldol reaction to generate initial chirality in the targeted mol. The geminal dichloromethane functionality was introduced by the addition of in situ-generated dichloromethyllithium to Weinreb’s amide functional group.

Journal of Organic Chemistry published new progress about Aldol addition, stereoselective. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, HPLC of Formula: 171877-39-7.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Abe, Hideki published the artcileTotal Synthesis of Catunaregin and Preliminary Evaluation of Its Antitumor Activity, Name: (S)-4-Benzylthiazolidine-2-thione, the main research area is catunaregin synthesis antitumor.

The total synthesis of catunaregin in both racemic and optically active forms was accomplished. The enantioselective synthesis uses the Evans aldol strategy, with an oxazolidinone or thiazolidinethione as the chiral auxiliary. The key features include a syn-selective aldol reaction to form the Evans-syn or non-Evans-syn product, and a successive ketalization reaction of a furanyl diol derivative under acidic conditions. The biol. properties of the synthetic racemate and both enantiomers were evaluated against A549 and HL-60 human cancer cells.

European Journal of Organic Chemistry published new progress about Aldol addition, stereoselective. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Name: (S)-4-Benzylthiazolidine-2-thione.

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica