131121-29-4

Upstream product

• 158348-25-5 {(3aR,4R,5aS,8R,9aS,9bS)-4-[(E)-(S)-5-Benzyloxy-1-(tert-butyl-dimethyl-silanyloxy)-4-oxo-pent-2-enyl]-2,2-diethyl-octahydro-[1,3]dioxolo[4,5-d]pyrano[3,2-b]pyran-8-yl}-acetic acid methyl ester 
• 33985-40-9 (3aR,4S,6R,6aR)-tetrahydro-6-methoxy-2,2-dimethylfuro-[3,4-d][1,3]dioxole-4-carbaldehyde 
• 131121-18-1 (E)-ethyl 3-((3aR,4R,6R,6aR)-tetrahydro-4-methoxy-2,2-dimethylfuro[3,4-d][1,3]dioxol-6-yl)acrylate 
• 131121-23-8 (4R,5R)-5-((3aR,4R,6R,6aR)-6-Methoxy-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-2,2-dimethyl-[1,3]dioxolane-4-carbaldehyde 
• 131121-21-6 (4S,5R)-5-((3aR,4S,6R,6aR)-6-Methoxy-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-2,2-dioxo-2λ⁶-[1,3,2]dioxathiolane-4-carboxylic acid ethyl ester 
• 131121-22-7 Benzoic acid (1R,2R)-1-ethoxycarbonyl-2-hydroxy-2-((3aR,4R,6R,6aR)-6-methoxy-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-ethyl ester 
• 131121-19-2 (2R,3S)-2,3-Dihydroxy-3-((3aR,4R,6R,6aR)-6-methoxy-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-propionic acid ethyl ester 
• 131121-19-2 (2S,3S)-2,3-Dihydroxy-3-((3aR,4R,6R,6aR)-6-methoxy-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-propionic acid ethyl ester 
• 131121-31-8 (E)-5-[(3S,3aR,5S,6S,7R,7aR)-3,6,7-Triacetoxy-2-(3-benzyloxy-2-oxo-propyl)-hexahydro-furo[3,2-b]pyran-5-yl]-pent-2-enoic acid ethyl ester 
• 131121-24-9 Acetic acid (2S,3S,3aR,5S,6R,7R,7aR)-3,5,6-triacetoxy-2-(3-benzyloxy-2-oxo-propyl)-hexahydro-furo[3,2-b]pyran-7-yl ester 
• 131121-26-1 Acetic acid (2S,3S,3aR,5S,6S,7R,7aR)-3,6-diacetoxy-2-(3-benzyloxy-2-oxo-propyl)-5-(3-hydroxy-propyl)-hexahydro-furo[3,2-b]pyran-7-yl ester 
• 131121-25-0 Acetic acid (2S,3S,3aR,5S,6S,7R,7aR)-3,6-diacetoxy-5-allyl-2-(3-benzyloxy-2-oxo-propyl)-hexahydro-furo[3,2-b]pyran-7-yl ester 
• 131121-57-8 (E)-1-Benzyloxy-4-[(4S,5S)-5-((3aR,4R,6R,6aR)-6-methoxy-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-but-3-en-2-one 
• 131121-28-3 C₂₃H₂₈O₈ 

Relevant academic research and scientific papers

Halichondrin B: Synthesis of the C(1)-C(15) subunit

A short and efficient synthesis of the C(1)-C(15) subunit of halichondrin B in its natural configuration is described. The polycyclic caged ketal 3, containing nine asymmetric centers, is prepared in 14 steps from α-D-glucoheptonic acid γ-lactone (7). Key steps in the two similar routes described include EtMgBr-promoted pinacol ring expansions of hydrory mesylates 23 and 34. intramolecular Michael additions of 29 and 37, and a one-pot, HF-induced conversion of 4 to 3 involving in situ silyl ether cleavage, acetal hydrolysis, Michael addition, and caged ketal formation. Alternative protocols for carbinol inversion at C(11), one early and one late in the synthetic sequence, are also described.

Total synthesis of halichondrins: Enantioselective construction of a homochiral pentacyclic C1-C15 intermediate from D-ribose

The remarkable heterobicyclization of a homochiral acyclic precursor, derived diastereoselectively from D-ribose, is exploited in a synthesis of the intricate multicyclic poly ether C1 to C15 segment of halichondrins.