289472-91-9

Upstream product

• 6638-79-5 N,O-dimethylhydroxylamine*hydrochloride 
• 3112-85-4 methylphenylsulfonate 
• 289472-99-7 (2S)-2-(4-methoxy-phenyl)-methyloxy-4-phenyl-sulphonyl-butanal 
• 289472-97-5 (S)-4-Benzenesulfonyl-1-(tetrahydro-pyran-2-yloxy)-butan-2-ol 
• 394657-54-6 (S)-4-Benzenesulfonyl-2-(4-methoxy-benzyloxy)-butan-1-ol 
• 289472-98-6 (2S)-2-(4-methoxy-phenyl)-methyloxy-4-phenyl-sulphonyl-1-(2-tetrahydro-pyranyl)-oxybutane 

Downstream Products

• 289473-02-5 (1E,3S,4S)-6-benzenesulfonyl-4-(4-methoxy-benzyloxy)-1-[(2S)-4-methyl-3,6-dihydro-2H-pyran-2-yl]-hex-1-en-3-ol 
• 289473-04-7 (3S,4S)-6-Benzenesulfonyl-4-(4-methoxy-benzyloxy)-1-((S)-4-methyl-3,6-dihydro-2H-pyran-2-yl)-hex-1-yn-3-ol 
• 312695-82-2 (2S)-2-{(E)-2-[(4S,5S)-5-(2-benzenesulfonyl-ethyl)-2-(4-methoxy-phenyl)-[1,3]dioxolan-4-yl]-vinyl}-4-methyl-3,6-dihydro-2H-pyran 
• 312695-76-4 (3S,4S,5E)-1-benzenesulfonyl-4-(4-methoxy-benzyloxy)-6-[(2S)-4-methyl-3,6-dihydro-2H-pyran-2-yl]-hex-5-en-3-ol 
• 349539-62-4 2-{(2R,6R)-6-[(7E,12E)-(2S,6S,10S,11S)-10-(4-Methoxy-benzyloxy)-6-methoxymethoxy-2-methyl-13-((S)-4-methyl-3,6-dihydro-2H-pyran-2-yl)-4-methylene-11-(tetrahydro-pyran-2-yloxy)-trideca-7,12-dienyl]-5,6-dihydro-2H-pyran-2-yl}-ethanol 
• 349539-60-2 (1E,6E)-(3S,4S,8S,12S)-13-{(2R,6R)-6-[2-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-3,6-dihydro-2H-pyran-2-yl}-4-(4-methoxy-benzyloxy)-8-methoxymethoxy-12-methyl-1-((S)-4-methyl-3,6-dihydro-2H-pyran-2-yl)-10-methylene-trideca-1,6-dien-3-ol 
• 394657-50-2 4-{6-[10-(4-methoxy-benzyloxy)-6-methoxymethoxy-2-methyl-13-(4-methyl-3,6-dihydro-2H-pyran-2-yl)-4-methylene-11-(tetrahydro-pyran-2-yloxy)-trideca-7,12-dienyl]-5,6-dihydro-2H-pyran-2-yl}-but-2-enoic acid 2-trimethylsilanyl-ethyl ester 
• 289473-01-4 (4S)-6-benzenesulfonyl-4-(4-methoxy-benzyloxy)-1-[(2S)-4-methyl-3,6-dihydro-2H-pyran-2-yl]-hex-1-yn-3-one 

Relevant academic research and scientific papers

Total synthesis of microtubule-stabilizing agent (-)-laulimalide

An enantioselective first total synthesis of laulimalide (1) is described. Laulimalide, a remarkably potent antitumor macrolide, has been isolated from the Indonesian sponge Hyattella sp. and the Okinawan sponge Fasciospongia rimosa. Laulimalide represents a new class of antitumor agents with significant clinical potential. The synthesis is convergent and involved the assembly of C3-C16 segment 4 and C17-C28 segment 5 by Julia olefination. The sensitive C2-C3 cis-olefin functionality was installed by Yamaguchi macrolactonization of a hydroxy alkynic acid followed by hydrogenation of the resulting alkynoic lactone over Lindlar's catalyst. Initial attempts of intramolecular Still's variant of Horner - Emmons olefination between the C19-phosphonocetate and C3-aldehyde provided a 1:2 mixture of cis- and trans-macrolactones. The trans-isomer was photo-isomerized to a mixture of cis- and trans-isomers. The other key steps involved ring-closing olefin metathesis to construct both dihydropyran units, stereoselective anomeric alkylation to functionalize the dihydropyran ring, stereoselective reduction of the resulting alkynyl ketone to set the C20-hydroxyl stereochemistry, and a novel Julia olefination protocol for the installation of the C13-exomethylene unit. The sensitive epoxide at C16-C17 was introduced in a highly stereoselective manner by Sharpless epoxidation at the final stage of the synthesis.

Synthetic studies of antitumor macrolide laulimalide: A stereoselective synthesis of the C17-C28 segment

A stereoselective synthesis of the C17-C28 segment of the potent antitumor macrolide, laulimalide has been accomplished. The key steps are a ring-closing olefin metathesis to construct the dihydropyran unit, nucleophilic addition of an alkynyl anion to the Weinreb amide, stereoselective reduction of the resulting ketone to set the C20-hydroxyl stereochemistry, and elaboration of the C21-C22 trans-olefin geometry. (C) 2000 Elsevier Science Ltd.