81997-75-3

Upstream product

• 3699-66-9 ethyl 2-diethoxyphosphorylpropionate 
• 1707-77-3 1,2:5,6-di-O-isopropylidene-D-mannitol 
• 21382-82-1 (carbethoxyethylidene)triphenylphosphorane 
• 22323-80-4 (4S)-2,2-dimethyl-[1,3]dioxolane-4-carbaldehyde 
• 535-11-5 Ethyl 2-bromopropionate 
• 15186-48-8 2,3-isopropylidene-glyceraldehyde 
• 2985-33-3 monoethyl methylmalonate 

Downstream Products

• 93635-76-8 (2S,3R)-3-[(4R)-2,2-dimethyl-[1,3]dioxolane-4-yl]-2,3-dihydroxy-2-methylpropionic acid ethyl ester 
• 93636-26-1 ethyl 4,5-O-isopropylidene-2-C-methyl-D-xylonate 
• 93635-77-9 C₂₇H₂₂O₈ 
• 498-16-8 (R)-5-methyl-2-(prop-1-en-2-yl)hex-4-en-1-ol 
• 108404-54-2 (3S,4S)-5-benzyloxy-4-hydroxy-3-isopropenylpentanoic acid lactone 
• 108404-44-0 (3R,4S)-5-benzyloxy-4-hydroxy-3-isopropenylpentanoic acid lactone 
• 108404-45-1 (3R,4S)-5-benzyloxy-3-(1-chloro-1-1-methylethyl)-4-hydroxypentanoic acid lactone 
• 108404-47-3 (1S,3R)-3-(2-benzyloxy-1-hydroxyethyl)-2,2-dimethylcyclopropanecarboxylic acid lactone 
• 219926-62-2 (4S)-2,2-Dimethyl-4-[(Z)-2-methyl-3-phenylsulfonylprop-1-enyl]-1,3-dioxolane 
• 219926-65-5 (2E,4E)-5-Benzenesulfonyl-4-methyl-penta-2,4-dien-1-ol 
• 219926-66-6 (2E,4Z)-5-Benzenesulfonyl-4-methyl-penta-2,4-dien-1-ol 
• 425427-13-0 (3R,4R,4'S)-2-N-benzyl-3-(2',2'-dimethyl-1',3'-dioxolan-4'-yl)-4-methyl-1,2-isoxazolidin-5-one 

Relevant academic research and scientific papers

Preparation method of 2-C-methyl-4, 5-O-(1-methylvinyl)-D-arabitic acid ethyl ester

The invention discloses a preparation method of 2-C-methyl-4, 5-O-(1-methylvinyl)-D-arabitic acid ethyl ester (formula I). Compared with the prior art, the preparation method has short reaction steps,reduces the use of organic solvents and generation of solid waste. At the same time, the used reagents are all conventional reagents, the method has the characteristics of simple operation, mild reaction conditions and environmental friendliness, and can achieve industrial preparation of 2-C-methyl-4, 5-O-(1-methylvinyl)-D-arabitic acid ethyl ester.

A Synthesis of (-)-(R)- and (+)-(S)-Lavandulol, (+)-Lavandulyl 2-methylbutanoate, and (+)-lavandulyl senecioate through orthoester johnson-claisen rearrangement

An efficient synthesis of (-)-(R)- and (+)-(S)-lavandulol, (+)-lavandulyl 2-methylbutanoate and (+)-lavandulyl senecioate is presented in this paper. The synthetic strategy features a chiral-pool approach to an allyl alcohol intermediate, and an orthoester Johnson-Claisen rearrangement as the key step. An efficient synthesis of (-)-(R)- and (+)-(S)-lavandulol, (+)-lavandulyl 2-methylbutanoate and (+)-lavandulyl senecioate is presented. The synthetic strategy features a chiral-pool approach to an allyl alcohol intermediate, and an orthoester Johnson-Claisen rearrangement as the key step. Copyright

Spongipyran synthetic studies. Total synthesis of (+)-spongistatin 2

Evolution of a convergent synthetic strategy to access (+)-spongistatin 2 (2), a potent cytotoxic marine macrolide, is described. Highlights of the synthesis include: development of a multicomponent dithiane-mediated linchpin union tactic, devised and implemented specifically for construction of the spongistatin AB and CD spiro ring systems; application of a CaII ion controlled acid promoted equilibration to set the thermodynamically less stable axial-equatorial stereogenicity in the CD spiroketal; use of sulfone addition/Julia methylenation sequences to unite the AB and CD fragments and introduce the C(44)-C(51) side chain; and fragment union and final elaboration to (+)-spongistatin 2 (2) exploiting Wittig olefination to unite the advanced ABCD and EF fragments, followed by regioselective Yamaguchi macrolactonization and global deprotection. Correction of the CD spiro ring stereogenicity was subsequently achieved via acid equilibration in the presence of CaII ion to furnish (+)-spongistatin 2 (2). The synthesis proceeded with a longest linear sequence of 41 steps.

Selective conjugate addition of nitromethane to enoates derived from D-mannitol and L-tartaric acid

The conjugate addition of nitromethane to enoates prepared from D-(+)-mannitol, substituted at the α-position by a methyl or a benzyl group, was investigated. While excellent syn-selectivity (d.e. >90%) was obtained from α-benzyl enoates (used as a mixture of epimers, E/Z=1.8:1), for α-methyl enoates the selectivity depended on the stereochemistry of the double bond in the acceptor (d.e. >90% for the (Z)-enoate and 50% for the (E)-enoate). In all cases, a mixture of epimers was formed at the newly generated stereocenter at the α-position. The epimeric syn-adducts were transformed into the corresponding pure α,β,γ-trisubstituted γ-butyrolactones by cyclization in acid medium followed by epimerization of the stereocenter at the α-position in DBU/CH2Cl2. When enoates derived from L-tartaric acid were used as acceptors, syn-selective conjugate additions were also observed (d.e. >90% for the (Z)-isomer and 50% for the (E)-isomer). The configuration at the newly generated stereogenic centers were assigned based on X-ray analyses, 1H-1H coupling constants and NOE experiments in NMR spectroscopy.

Stereoselective synthesis of 1-hydroxymethyl-4-phenylsulfonylbutadienes

Stereoselective syntheses of 1-hydroxymethyl-4-phenylsulfonylbutadienes were achieved from unsaturated sulfones which were easily obtained from D-Mannitol.

CHIRAL ROUTE TO cis-CARONALDEHYDE FROM D-MANNITOL

A chiral route to cis-caronaldehyde, a key intermediate of cis-pyrethroid insecticides as well as an efficient resolving agent for secondary alcohols, has been developed using D-mannitol as the starting material employing a sequential one-pot sodium periodate cleavage and Horner-Emmons condensation in an aqueous medium as the key stage.