Day: October 12, 2022

Abraham, Elin; Candela-Lena, Jose I.; Davies, Stephen G.; Georgiou, Matthew; Nicholson, Rebecca L.; Roberts, Paul M.; Russell, Angela J.; Sanchez-Fernandez, Elena M.; Smith, Andrew D.; Thomson, James E. published the artcile< Asymmetric synthesis of N,O,O,O-tetra-acetyl D-lyxo-phytosphingosine, jaspine B (pachastrissamine) and its C(2)-epimer>, HPLC of Formula: 104322-63-6, the main research area is phytosphingosine jaspine B pachastrissamine amino alc asym preparation; ester unsaturated stereoselective conjugate addition oxidation intramol cyclization.

The highly diastereoselective conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)amide to a γ-silyloxy-α,β-unsaturated ester and in situ enolate oxidation with (+)-(camphorsulfonyl)oxaziridine has been used as the key step in the asym. synthesis of N,O,O,O-tetra-acetyl D-lyxo-phytosphingosine I, jaspine B (pachastrissamine) II and its C(2)-epimer III.

Tetrahedron: Asymmetry published new progress about Amino alcohols, chiral Role: PRP (Properties), RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, HPLC of Formula: 104322-63-6.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Davies, Stephen G.; Foster, Emma M.; Lee, James A.; Roberts, Paul M.; Thomson, James E. published the artcile< Stereospecific Cyclization Strategies for α,ε-Dihydroxy-β-amino Esters: Asymmetric Syntheses of Imino and Amino Sugars>, Quality Control of 104322-63-6, the main research area is amino acid alditol imino preparation stereoselective cyclization camphorsulfonyl oxaziridine.

A range of biol. significant imino and amino sugars [1,4-dideoxy-1,4-imino-D-allitol, 3,6-dideoxy-3,6-imino-L-allonic acid, (3R,4S)-3,4-dihydroxy-L-proline, 1,5-anhydro-4-deoxy-4-amino-D-glucitol, and 1,5-anhydro-4-deoxy-4-amino-L-iditol] has been prepared via stereospecific cyclization of α,ε-dihydroxy-β-amino esters. These substrates are readily prepared via conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)amide to enantiopure α,β-unsaturated esters (β-substituted with cis- and trans-dioxolane units) coupled with in situ enolate oxidation with camphorsulfonyl-oxaziridine (CSO). Activation of the ε-hydroxyl group allowed cyclization to either the corresponding pyrrolidine or the tetrahydropyran scaffold, with the course of the cyclization process being dictated by the relative configuration of the dioxolane unit. When the α,ε-dihydroxy-β-amino ester bears a cis-dioxolane unit, cyclization occurs upon attack of the β-amino substituent to give the corresponding pyrrolidine after in situ N-debenzylation. In contrast, when the α,ε-dihydroxy-β-amino ester bears a trans-dioxolane unit, cyclization occurs upon attack of the α-hydroxyl substituent to give the corresponding tetrahydropyran.

Journal of Organic Chemistry published new progress about Alditols Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Quality Control of 104322-63-6.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Wei, Yen; Bakthavatchalam, R.; Jin, Xian Ming; Murphy, Christopher K.; Davis, Franklin A. published the artcile< Effect of aggregation on stereochemistry and mechanism of asymmetric oxidation of the lithium enolate of methyl 3,3-dimethylbutanoate in the solid state and in solution>, Name: (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide, the main research area is asym oxidation lithium enolate mechanism; enantiopure camphorylsulfonyloxaziridine oxidation lithium enolate; stereoselective oxidation lithium enolate; solid state oxidation lithium enolate.

Oxidation of the title enolate by enantiopure (camphorylsulfonyl)oxaziridines in THF afforded α-hydroxy ester with 53-73% ee, but the product from the solid state reactions was racemic. The results suggest that the enolate exists and reacts as an aggregate in the solid state reactions.

Tetrahedron Letters published new progress about Oxidation. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Name: (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Davis, Franklin A.; Kumar, Anil published the artcile< Kinetic resolution in the asymmetric hydroxylation of enolates. Stereospecific synthesis of (2S,3R)-(-)-verrucarinolactone>, Recommanded Product: (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide, the main research area is methylvalerolactone asym hydroxylation camphorylsulfonyloxaziridine; verrucarinolactone stereoselective preparation.

Asym. hydroxylation of (±)-3-methylvalerolactone (I; R = H) with substoichiometric amounts of the (-)-(camphorylsulfonyl)oxaziridine affords (2S,3R)-(-)-verrucarinolactone (I; R = HO) in 60% ee, which on crystallization is obtained enantiomerically pure. This result not only represents a highly efficient stereospecific synthesis of an important lactone, but also demonstrates the application of kinetic resolution and asym. hydroxylation in the synthesis of enantiomerically enriched α-hydroxy carbonyl compounds having multiple stereocenters.

Journal of Organic Chemistry published new progress about 104322-63-6. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Recommanded Product: (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Davis, Franklin A.; Towson, James C.; Weismiller, Michael C.; Lal, Sankar; Carroll, Patrick J. published the artcile< Chemistry of oxaziridines. 11. (Camphorylsulfonyl)oxaziridine: synthesis and properties>, Recommanded Product: (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide, the main research area is camphorylsulfonyloxaziridine preparation oxidation sulfide; crystal structure camphorylsulfonyloxaziridine; mol structure camphorylsulfonyloxaziridine; oxaziridine camphorylsulfonyl preparation crystal structure; asym synthesis sulfoxide.

(+)- And (-)-(camphorylsulfonyl)oxaziridines (+)- and (-)-I are prepared in 3 steps from (+)- and (-)-camphorsulfonyl chlorides in 67% overall yield. In contrast to other optically active sulfonimines, which give on oxidation mixtures of oxaziridine diastereoisomers, oxidation of camphorsulfonimine (-)-II [the precursor to (+)-I] with oxone produces only a single isomer in >95% yield. In the asym. oxidation of prochiral sulfides by I the enantioselectivities are lower than those reported for oxidation by optically active N-sulfamyloxaziridine (5-73 vs. 35-60% enantiomeric excess). This difference is discussed in terms of different active site structures for the 2 oxaziridines. The configuration of the oxaziridine 3-membered ring in I controls the configuration of the product, with (+)-I and (-)-I giving the opposite senses of asym. induction. I does not readily oxidize amines or epoxidize alkenes. Oppolzer’s sultam chiral auxiliary [(-)-III] is prepared in 92% yield by hydride reduction of (-)-II. The structure of (+)-I was determined by x-ray crystallog.

Journal of the American Chemical Society published new progress about Crystal structure. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Recommanded Product: (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Davis, Franklin A.; Lal, G. Sankar; Wei, Jia published the artcile< Stereo- and regioselective formation of silyl enol ethers via oxidation of vinyl anions>, Electric Literature of 104322-63-6, the main research area is silyl enol ether stereoselective preparation; oxidation vinyl bromide derivative stereoselective; vinyllithium stereoselective oxidation.

Oxidation of E- and Z-vinyllithiums, R1CR2:CR3Li (R1-R3 = Ph, Me, Et, etc.), with silyl peroxides, RSiMe2OOSiMe2R (R = Me, Me3C), affords silyl enol ethers, R1CR2:CR3OSiMe2R, in good to excellent yield with retention of configuration. This methodol. represents a useful new procedure for the stereo- and regioselective synthesis of ketone enolates.

Tetrahedron Letters published new progress about Oxidation, stereoselective. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Electric Literature of 104322-63-6.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Bunnage, Mark E.; Davies, Stephen G.; Goodwin, Christopher J. published the artcile< Asymmetric synthesis of allophenylnorstatine>, Computed Properties of 104322-63-6, the main research area is asym synthesis allophenylnorstatine; norstatine allophenyl asym synthesis.

The title compound (I), a component of the HIV-1 protease inhibitor kynostatin, has been prepared via a tandem conjugate addition-electrophilic hydroxylation strategy using lithium (S)-(α-methylbenzyl)benzylamide and (+)-(camphorsulfonyl)oxaziridine. The effects of mol. recognition and enolate geometry on the selectivity of the reaction are discussed.

Synlett published new progress about Stereoselective synthesis. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Computed Properties of 104322-63-6.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

McClure, Cynthia K.; Grote, Christopher W. published the artcile< α,β-Functionalization of enones via pentacovalent oxaphospholenes>, Safety of (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide, the main research area is oxaphospholene functionalization enone; phosphonate keto acylvinyl.

2,2,2-Triethoxy-1,2λ5-oxaphospholene reacts under mild, neutral conditions with bromine, dialkyl azodicarboxylates, and oxaziridines to produce β-heteroatom substituted γ-ketophosphonates and β-acyl vinyl phosphonate in high yields.

Tetrahedron Letters published new progress about 104322-63-6. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Safety of (4aS,7R,8aS)-9,9-Dimethyltetrahydro-4H-4a,7-methanobenzo[c][1,2]oxazireno[2,3-b]isothiazole 3,3-dioxide.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Towson, James C.; Weismiller, Michael C.; Lal, G. Sankar; Sheppard, Aurelia C.; Kumar, Anil; Davis, Franklin A. published the artcile< Synthesis of (+)-(2R,8aS)-10-(camphorylsulfonyl)oxaziridine>, Reference of 104322-63-6, the main research area is camphorylsulfonyloxaziridine; oxaziridine camphorylsulfonyl.

Amidation of (+)-10-camphosulfonyl chloride by NH4OH in CH2Cl2 gave 90% (+)-(1S)-1-camphorsulfonamide which underwent Amberlyst 15 catalyzed cyclocondensation in PhMe to give 90-95% imine I. The last was treated with aqueous oxone and K2CO3 to give 84% title compound II.

Organic Syntheses published new progress about 104322-63-6. 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Reference of 104322-63-6.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com

Escalante, Jaime; Juaristi, Eusebio published the artcile< Enantioselective synthesis of β-amino acids. 6. High 1,2-stereoinduction in the preparation of enantiopure 2(R)-hydroxy-3(R)-N-benzoylamino-3-phenylpropionic acid (like stereoisomer of Taxol's side chain)>, Formula: C10H15NO3S, the main research area is stereoselective hydroxylation phenylperhydropyrimidinone camphor oxaziridine; pyrimidinone phenylperhydro stereoselective hydroxylation oxaziridine; asym synthesis phenylisoserine.

The remarkably high 1,2-stereoinduction encountered in the hydroxylation of 6(S)-phenylperhydropyrimidin-4-one I allows for the preparation of enantiopure N-benzoyl (2R,3R)-3-phenylisoserine (II), the like stereoisomer of taxol’s C-13 side chain.

Tetrahedron Letters published new progress about Amino acids, hydroxy Role: SPN (Synthetic Preparation), PREP (Preparation). 104322-63-6 belongs to class isothiazole, and the molecular formula is C10H15NO3S, Formula: C10H15NO3S.

Referemce:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com