Day: November 10, 2022

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

Aursnes, M. published the artcileStereoselective synthesis of protectin D1: a potent anti-inflammatory and proresolving lipid mediator, Safety of (S)-4-Benzylthiazolidine-2-thione, the main research area is protectin D1 stereoselective synthesis antiinflammatory proresolving lipid mediator; Wittig reaction Evans Aldol hydrogenation Lindlar catalyst chiral auxiliary.

A convergent stereoselective synthesis of the potent anti-inflammatory, proresolving and neuroprotective lipid mediator protectin D1 has been achieved in 15% yield over eight steps. The key features were a stereocontrolled Evans-aldol reaction with Nagao’s chiral auxiliary and a highly selective Lindlar reduction of internal alkyne (I) , allowing the sensitive conjugated E,E,Z-triene to be introduced late in the preparation of protectin D1. The UV and LC/MS-MS data of synthetic protectin D1 matched those obtained from endogenously produced material.

Organic & Biomolecular 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, Safety of (S)-4-Benzylthiazolidine-2-thione.

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

Lu, Cui-Fen published the artcileStereoselective synthesis of (R)-10-methyltridecan-2-one, the sex pheromone of the southern corn rootworm, using (4S)-benzylthiazolidinethione as a chiral auxiliary, Category: thiazole, the main research area is methyltridecanone stereoselective synthesis Michael addition benzylthiazolidinethione chiral auxiliary.

The stereoselective synthesis of (R)-10-methyltridecan-2-one, the sex pheromone of the southern corn rootworm, was carried out in 20.7% overall yield based on (4S)-benzylthiazolidine-2-thione (five steps). In the crucial step, the stereogenic center was generated by an asym. Michael addition using enantiomerically pure (4S)-benzylthiazolidine-2-thione as a chiral auxiliary.

Tetrahedron: Asymmetry published new progress about Michael reaction, stereoselective. 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Category: thiazole.

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

Wu, Yikang published the artcileEnantioselective Total Synthesis of (+)-Brefeldin A and 7-epi-Brefeldin A, Application In Synthesis of 171877-39-7, the main research area is asym synthesis brefeldin a epibrefeldin stereoselective aldol chiral auxiliary; chiral auxiliary oxazolidinone thiazolidinethione stereoselective aldol reaction protecting group; stereoselective reduction elimination solvent effect asym synthesis brefeldin a; intramol Mukaiyama aldol condensation stereoselective Michael asym synthesis brefeldin.

A convergent enantioselective route to brefeldin A (I) and 7-epi-BFA was developed. The key C-4/C-5 chiral centers were established by using chiral auxiliary induced intermol. asym. aldolization in the presence of TiCl4 and TMEDA. The results with the thiazolidinethione/TiCl4 mediated intermol. asym. aldolization added some new information about the scope and limitations to the existing knowledge of that type of reactions (which so far was essentially limited to the reactions with N-propionyl thiazolidinethiones). During the course a method for protecting the liable aldol hydroxyl groups by using inexpensive TBSCl in DMF with 2,6-lutidine as the base was developed to replace the otherwise unavoidable TBSOTf procedure. Due to the excessive steric hindrance, removal of the auxiliary was much more difficult than most literature cases. Cleavage of the oxazolidinone by reduction was almost impossible. The thiazolidinethione auxiliary was relatively easier to remove. However, several reactions reported for facile removal of thiazolidinethione auxiliaries in the literature still failed. Reductive removal of the thiazolidinethione auxiliary was most effectively realized with LiBH4 in di-Et ether in the presence of 1 equiv of MeOH (a modification of a literature procedure for removal of oxazolidinone auxiliaries in less hindered substrates). Apart from the auxiliary removal, oxidation of the alc. into aldehyde and the deprotection of the dithiolane protecting group were also rather difficult in the present context. A range of methods were screened before final solutions were found. The five-membered ring was constructed by employing an intramol. Mukaiyama reaction after many attempts with the intramol. aldolization under a variety of conditions failed. The rate of elimination of the alkoxyl to form the α,β-double bond of a key intermediate cyclopentenone with DBU was highly solvent dependent (very sluggish in CH2Cl2 but rather fast in MeOH). Introduction of the lower chain (which was synthesized by using a Jacobsen KHR to establish the C-15 chirality) was achieved through a Michael addition similar to the precedents in the literature. It has not been noticed before that the yield of this Michael reaction could be dramatically raised by using 3 equiv of the copper-lithium reagent. Reduction of the C-7 carbonyl was apparently more difficult than similar cases in the literature. After examination of many reagents under various conditions, it was found that the best reagent for yielding the α-isomer was (S)-2-methyl-CBS-borolidine/BH3 and that for the β-isomer was L-Selectride. The α- and β-isomers were then further elaborated into (+)-brefeldin A and 7-epi-BFA, resp. An unexpected yet very interesting solubility difference between BFA and 7-epi-BFA was also observed

Journal of Organic Chemistry published new progress about Aldol condensation, 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

Bumbu, Valentina D. published the artcileKinetic Resolution of N-Acyl-Thiolactams via Catalytic Enantioselective Deacylation, Computed Properties of 171877-39-7, the main research area is kinetic resolution acyl thiolactam catalytic enantioselective deacylation benzotetramisole.

Methanolysis of N-acylthiazolidin-2-thiones and -oxazolidin-2-thiones in the presence of acyl transfer catalyst benzotetramisole (BTM) proceeds in a highly enantioselective fashion thus enabling kinetic resolution of these substrates [e.g., treatment of thiolactam (±)-I with MeOH, catalyst II and PhCO2H afforded (S)-III + (R)-I with s = 84].

Organic Letters published new progress about Acylation catalysts (stereoselective). 171877-39-7 belongs to class thiazole, name is (S)-4-Benzylthiazolidine-2-thione, and the molecular formula is C10H11NS2, Computed Properties of 171877-39-7.

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

Jiang, Cheng published the artcileDesign of novel thiazole bearing pyrazole derivatives and their dual activities as ACE inhibitors and calcium channel blockers in cardiovascular disease, Product Details of C9H7N3O2S, the main research area is cardiovascular disease thiazole pyrazole derivative ACE inhibitor calcium channel.

In an attempt to develop drugs for cardio-vascular disease, present manuscript deal with the development of dual acting agents targeting angiotensin converting enzyme (ACE) and calcium channel to treat hypertension. These mols. were developed via efficient multi-step synthetic route in excellent yield. In ACE inhibitors assay, these compounds showed considerable percentage of inhibition (32-94 %) with IC50 = 1.2 and 1.5 μM for most promising compound 6e and 6o, resp. In mol. docking study with ACE, compound 6e revealed similar fashion of mol. interaction with catalytic residues His353, Ala 354, Tyr 523, Tyr 520, and Glu 152, comparable with standard lisinopril. Addnl., in rat aortic strip model, these mols. significantly induce vasorelaxation via inhibiting Ca2+ channel in dose dependent manner.

Latin American Journal of Pharmacy published new progress about Angiotensin-converting enzyme inhibitors. 90323-06-1 belongs to class thiazole, name is 4-(2-Nitrophenyl)thiazole-2-amine, and the molecular formula is C9H7N3O2S, Product Details of C9H7N3O2S.

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

Breckenridge, Robin J. published the artcileInhibition of [3H]GABA binding to postsynaptic receptors in human cerebellar synaptic membranes by carboxyl and amino derivatives of GABA, Recommanded Product: 2-(2-Phenylthiazol-4-yl)acetic acid, the main research area is GABA receptor structure activity.

Fifty synthetic analogs of GABA [56-12-2] were tested for their ability to interact with GABA receptors, using [3H]GABA binding to human cerebellar membranes as an in vitro model. The most active compounds were aliphatic and heterocyclic aminosulfonic acids. Compounds with highly substituted n atoms were only weakly active unless a long alkyl chain, which can interact with the postsynaptic membrane, was present. A pyramidal N atom is favored for binding of GABA analogs to human cerebellar membranes.

Journal of Neurochemistry published new progress about GABA receptors Role: BIOL (Biological Study). 16441-28-4 belongs to class thiazole, name is 2-(2-Phenylthiazol-4-yl)acetic acid, and the molecular formula is C11H9NO2S, Recommanded Product: 2-(2-Phenylthiazol-4-yl)acetic acid.

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

Baiget, Jessica published the artcileOn the influence of chiral auxiliaries in the stereoselective cross-coupling reactions of titanium enolates and acetals, Safety of (S)-4-Benzylthiazolidine-2-thione, the main research area is acylthiazolidinethione titanium enolate coupling acetal.

Titanium enolates from chiral N-propanoyl-1,3-thiazolidine-2-thiones containing bulky substituents at C-4 turned out to be excellent platforms to get highly stereocontrolled cross-coupling reactions with acetals. Related oxazolidinethiones also afforded good results, but the corresponding oxazolidinones were completely unselective for such reactions, which proves that an exocyclic C=S bond is essential to attain a synthetically useful stereocontrol.

Tetrahedron published new progress about Acetals Role: RCT (Reactant), RACT (Reactant or Reagent). 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