Tag: M.W=150-200

Prasanth, C. P.; Joseph, Ebbin; Abhijith, A.; Nair, D. S.; Ibnusaud, Ibrahim; Raskatov, Jevgenij; Singaram, Bakthan published the artcile< Stabilization of NaBH4 in Methanol Using a Catalytic Amount of NaOMe. Reduction of Esters and Lactones at Room Temperature without Solvent-Induced Loss of Hydride>, COA of Formula: C6H10O5, the main research area is sodium borohydride methanol catalysis reduction ester lactone.

Rapid reaction of NaBH4 with MeOH precludes its use as a solvent for large-scale ester reductions We have now learned that a catalytic amount of NaOMe (5 mol %) stabilizes NaBH4 solutions in methanol at 25 °C and permits the use of these solutions for the reduction of esters to alcs. The generality of this reduction method was demonstrated using 22 esters including esters of naturally occurring chiral γ-butyrolactone containing dicarboxylic acids. This method permits the chemoselective reductions of esters in the presence of cyano and nitro groups and the reductive cyclization of a pyrrolidinedione ester to a fused five-membered furo[2,3-b]pyrrole and a (-)-crispine A analog in high optical and chem. yields. Lactones, aliphatic esters, aromatic esters containing electron-withdrawing groups, and heteroaryl esters are reduced more rapidly than aryl esters containing electron-donating groups. The 11B NMR spectrum of the NaOMe-stabilized NaBH4 solutions showed a minor quartet due to monomethoxyborohydride (NaBH3OMe) that persisted up to 18 h at 25 °C. We postulate that NaBH3OMe is probably the active reducing agent. In support of this hypothesis, the activation barrier for hydride transfer from BH3(OMe)- onto benzoic acid Me ester was calculated as 18.3 kcal/mol.

Journal of Organic Chemistry published new progress about Aliphatic esters Role: RCT (Reactant), RACT (Reactant or Reagent). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, COA of Formula: C6H10O5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Gualtierotti, Jean-Baptiste; Pasche, Delphine; Wang, Qian; Zhu, Jieping published the artcile< Phosphoric acid catalyzed desymmetrization of bicyclic bislactones bearing an all-carbon stereogenic center: Total syntheses of (-)-rhazinilam and (-)-leucomidine B>, HPLC of Formula: 30095-98-8, the main research area is bicyclic bislactone alc desymmetrization ring opening phosphate catalyst; rhazinilam asym total synthesis; leucomidine B asym total synthesis; alkaloids; natural products; organocatalysis; synthetic methods; total synthesis.

In the presence of a catalytic amount of an imidodiphosphoric acid, enantioselective desymmetrization of bicyclic bislactones by reaction with alcs. took place smoothly to afford enantiomerically enriched monoacids having an all-C stereogenic center. Concise catalytic enantioselective syntheses of both (-)-rhazinilam and (-)-leucomidine B were subsequently developed using Me (S)-4-ethyl-4-formylpimelate monoacid as a common starting material.

Angewandte Chemie, International Edition published new progress about Alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 30095-98-8 belongs to class esters-buliding-blocks, and the molecular formula is C9H9NO4, HPLC of Formula: 30095-98-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

White, James D.; Lincoln, Christopher M.; Yang, Jongtae; Martin, William H. C.; Chan, David B. published the artcile< Total Synthesis of Solandelactones A, B, E, and F Exploiting a Tandem Petasis-Claisen Lactonization Strategy>, Application In Synthesis of 617-55-0, the main research area is solandelactone A B E F total synthesis; Petasis Claisen lactonization tandem total synthesis solandelactone; Nozaki Hiyama Kishi coupling total synthesis solandelactone; Simmons Smith cyclopropanation total synthesis solandelactone; methylenation Petasis total synthesis solandelactone.

Solandelactones A, B, E, and F I (R = α-OH, R1 = H; R = β-OH, R1 = H; R = α-OH, R12 = bond; R = β-OH, R12 = bond, resp.) were synthesized using Nozaki-Hiyama-Kishi coupling of iododiene (3S,1E,5Z)-ICH:CHCH(OH)CH2CH:CH(CH2)4Me with aldehydes II obtained by oxidation of the corresponding alcs. Key steps in the synthesis of the latter alcs. (i) a Nagao asym. acetate aldol reaction of aldehyde (E)-Me3CPh2SiOCH2CH:CHCHO with thionothiazolidine III to set in place an alc. that becomes the (7S) lactone center of solandelactones, (ii) a Simmons-Smith cyclopropanation of (3R,4E)-Me3CPh2SiOCH2CH:CHCH(OH)CH2CON(MeO)Me directed by this alc., and (iii) Petasis methylenation of cyclic carbonate IV in tandem with a Claisen rearrangement that generates the octenalactone portion of solandelactones. Synthesis of solandelactones A, B, E, and F confirmed their gross structure and absolute configuration at C7, 8, 10, and 14 but showed that alc. configuration at C11 must be reversed in pairs, A/B and E/F, from the previous assignment made to these hydroid metabolites. A biogenesis of solandelactones is proposed for these C22 oxylipins that parallels a hypothesis put forward previously to explain the origin of C20 cyclopropane-containing algal products.

Journal of Organic Chemistry published new progress about Aldol addition, stereoselective (Nagao). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Application In Synthesis of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Rachedi, Khadidja Otmane; Ouk, Tan-Sothea; Bahadi, Rania; Bouzina, Abdeslem; Djouad, Seif-Eddine; Bechlem, Khaoula; Zerrouki, Rachida; Ben Hadda, Taibi; Almalki, Faisal; Berredjem, Malika published the artcile< Synthesis, DFT and POM analyses of cytotoxicity activity of α-amidophosphonates derivatives: Identification of potential antiviral O,O-pharmacophore site>, Reference of 2743-40-0, the main research area is acylaminoester preparation phosphorylation ethylphosphite; amidophosphonate preparation anticancer agent optimized geometry DFT; amino acid acylation phosphorylation reaction.

The authors studied the cytotoxic activity of three compounds prepared starting from amino acids. These derivatives were evaluated for their in vitro antitumor activity against human cell lines (PRI, K562 and JURKAT). Their cytotoxicity was also evaluated at different concentrations on several cell lines. However, DFT calculation was used to analyze the electronic and geometric characteristics. The HOMO, LUMO and gap energies were also deduced for the stable structure for each compound These results will be correlated with the exptl. values. The bioinformatic POM (Petra/Osiris/Molinspiration) analyses of the relative cytotoxicity of these derivatives are reported in comparison to Chlorambucil.

Journal of Molecular Structure published new progress about Amino acids Role: RCT (Reactant), RACT (Reactant or Reagent). 2743-40-0 belongs to class esters-buliding-blocks, and the molecular formula is C8H18ClNO2, Reference of 2743-40-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Manna, Kartic; Ganguly, Tanusree; Baitalik, Sujoy; Jana, Ranjan published the artcile< Visible-Light- and PPh3-Mediated Direct C-N Coupling of Nitroarenes and Boronic Acids at Ambient Temperature>, Electric Literature of 30095-98-8, the main research area is secondary amine photochem preparation triphenylphosphine mediator; nitroarene boronic acid intermol reductive amination.

Herein a metal-free, visible-light- and triphenylphosphine-mediated intermol., reductive amination between nitroarenes and boronic acids at ambient temperature without any photocatalyst is presented. Mechanistically, a slow reduction of nitroarenes to a nitroso and, finally, a nitrene intermediate occurs that leads to the amination product with concomitant 1,2-aryl/-alkyl migration from a boronate complex. A wide range of nitroarenes underwent C-N coupling with aryl-/alkylboronic acids providing high yields.

Organic Letters published new progress about Amination catalysts (photochem). 30095-98-8 belongs to class esters-buliding-blocks, and the molecular formula is C9H9NO4, Electric Literature of 30095-98-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Siddiqui, Hina; Shafi, Sarah; Ali, Hamad; Musharraf, Syed Ghulam published the artcile< Synthesis and Erythroid Induction Activity of New Thiourea Derivatives>, Name: 4-tert-Butylphenylisothiocyanate, the main research area is thiourea fetal Hb erythroid; HbF induction effect; Thiourea derivatives; cytotoxicity; erythroid induction activity; sickle-cell anemia and β-thalassemia; β-thalassemia.

The erythroid induction potential of newly synthesized thiourea derivatives Thiourea derivatives 1-27 were synthesized by using environmentally friendly methods and new compounds 3, 10 and 22 The structures of synthesized derivatives were deduced by using various spectroscopic techniques. These derivatives were then evaluated for their erythroid induction using the human erythroleukemic K562 cell line, as a model. The benzidine-H2O2 assay was used to evaluate erythroid induction, while HbF expression was studied through immunocytochem. using the Anti-HbF antibody. Cytotoxicity of compounds 1-27 was also evaluated on mouse fibroblast 3T3 cell line and cancer Hela cell line using MTT assay. All the compounds (1-27) have not been reported for their erythroid induction activity previously. Compounds 1, 2, and 3 were found to be the potent erythroid inducing agents with % induction of 45± 6.9, 44± 5.9, and 41± 6.1, at 1.56, 0.78, and 0.78 μM concentrations, resp., as compared to untreated control (12 ± 1 % induction). Furthermore, compound 1, 2, and 3 significantly induced fetal Hb the expression up to 4.2-fold, 4.06-fold, and 3.52-fold, resp., as compared to untreated control. Moreover, the compounds 1-4, 6-9, 11, 12, 15, 17, 19, 22, 23, and 25 were found to be non-cytotoxic against the 3T3 cell line. This study signifies that the compounds reported here may serve as the starting point for the designing and development of new fetal Hb inducers for the treatment of beta-hemoglobinopathies.

Medicinal Chemistry (Sharjah, United Arab Emirates) published new progress about Cytotoxicity. 19241-24-8 belongs to class esters-buliding-blocks, and the molecular formula is C11H13NS, Name: 4-tert-Butylphenylisothiocyanate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Saito, Seiki; Ishikawa, Teruhiko; Kuroda, Akiyoshi; Koga, Kazuya; Moriwake, Toshio published the artcile< A revised mechanism for chemoselective reduction of esters with borane-dimethyl sulfide complex and catalytic sodium tetrahydroborate directed by adjacent hydroxyl group>, Related Products of 617-55-0, the main research area is ester reduction chemoselectivity borane dimethyl sulfide; sodium borohydride reduction ester stereochem; chiral synthon.

The plausible mechanism for the reduction of the ester groups with a strong preference for one located α to the hydroxyl groups of (S)-malates and (R,R)-tartrate-based derivatives has been proposed together with some results with regard to its applications to the synthesis of chiral synthons. Thus, reduction of di-Et (S)-maleate with BH3·SMe2 in THF in the presence of catalytic NaBH4 gave 97% Et (3S)-3,4-dihydroxybutanoate.

Tetrahedron published new progress about Chiral synthons. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Related Products of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Dunn, A. D. published the artcile< Synthesis of new thiopyranopyridines>, Quality Control of 33402-75-4, the main research area is thiopyranopyridinecarboxylate; photochem bromination pyridinecarboxylate; bromomethylpyridinecarboxylate preparation substitution thioglycolate.

Thiopyranopyridinecarboxylates I and II (X, Y = CH, N; R = OH, NH2) are prepared from pyridine esters (e.g., III; R1 = Me, R2 = CO2Me; R1 = CO2Me, R2 = Me) and nitriles (e.g., III; R1 = Me, R2 = CN) by photochem. bromination, followed by substitution reaction of the resulting bromomethyl derivative with HSCH2CO2Me, and then base-induced intramol. cyclocondensation.

Journal fuer Praktische Chemie (Leipzig) published new progress about Cyclocondensation reaction, intramolecular. 33402-75-4 belongs to class esters-buliding-blocks, and the molecular formula is C8H9NO2, Quality Control of 33402-75-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Zheng, Ying; Jia, Yimin; Yuan, Yuan; Jiang, Zhong-Xing; Yang, Zhigang published the artcile< F--Free Deoxyhydrotrifluoromethylation of α-Keto Esters with Ph3P+CF2CO2-: Synthesis of α-CF3-Substituted Esters>, Reference of 617-55-0, the main research area is deoxyhydrotrifluoromethylation keto ester fluoromethylating reagent.

Trifluoromethylated compounds are usually obtained via trifluoromethylation reaction by the use of CF3SiMe3 and NaSO2CF3, Umemoto’s and Togni’s reagents. Here, an external fluorine anion-free direct deoxyhydrotrifluoromethylation of α-keto esters with a difluoromethylating reagent has been achieved, in which the employment of water can promote the dissociation of the CF2 group to form a CF3 moiety, which provides the successful transformation. The current protocol demonstrates one of the most practical approaches to generate α-trifluoromethyl esters with a broad substrate scope and high functional group compatibility, in which it is applicable to late-stage modification of biol. active compounds and can be readily scaled up. Mechanistic investigation reveals that an in situ-generated gem-difluoroalkene intermediate is decomposed by water, giving rise to acid fluoride and HF.

Journal of Organic Chemistry published new progress about Atom economy (and step economy). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Reference of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Sasaki, Ryosuke; Tanabe, Yoo published the artcile< Chiral synthesis of methyl (R)-2-Sulfanylcarboxylic esters and acids with optical purity determination using HPLC>, Name: (S)-Dimethyl 2-hydroxysuccinate, the main research area is sulfanylcarboxylic ester acid preparation enantioselective cyclocondensation; thiazolidinone preparation diastereoselective; 2-sulfanylmandelic ester; 2-sulfanylsuccinic ester; HPLC analysis; SN2 inversion; drug discovery; process chemistry; thiazolidin-4-one; thiolactic acid.

Accessible chiral synthesis of 3 types of (R)-2-sulfanylcarboxylic esters and acids were performed: (R)-2-sulfanylpropanoic (thiolactic) ester (53%, 98% ee) and acid (39%, 96% ee), (R)-2-sulfanylsuccinic diester (59%, 96% ee) and (R)-2-mandelic ester (78%, 90% ee) and acid (59%, 96% ee). The present practical and robust method involves (i) clean SN2 displacement of methanesulfonates of (S)-2-hydroxyesters by using com. available AcSK with tris(2-[2-methoxyethoxy]ethyl)amine and (ii) sufficiently mild deacetylation. The optical purity was determined by the corresponding (2R,5R)-trans-thiazolidin-4-one and (2S,5R)-cis-thiazolidin-4-one derivatives based on accurate high-performance liquid chromatog. anal. with high-resolution efficiency. The Ti(O-i-Pr)4 catalyst promoted smooth trans-cyclocondensation of (R)-2-sulfanylcarboxylic esters with available N-(benzylidene)methylamine to afford (2R,5R)-trans-thiazolidin-4-ones under neutral conditions without any racemization, whereas (2S,5R)-cis-thiazolidin-4-ones were obtained via cis-cyclocondensation and no catalysts. Direct high-performance liquid chromatog. of Me (R)-mandelate was also performed; however, the resolution efficiency was inferior to that of the thaizolidin-4-one derivatizations.

Chirality published new progress about Cyclocondensation reaction. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Name: (S)-Dimethyl 2-hydroxysuccinate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics