Synthesis of a highly functionalised AB taxane ring system: formation of the eight-membered ring by an efficient 8-exo-tet alkylation of an α-sulfonyl anion
作者:David Crich、Swaminathan Natarajan
DOI:10.1039/c39950000085
日期:——
An efficient, scalable route to a Taxol A ringsynthon has been developed; its successful elaboration to a highly functionalized AB system by means of a novel nucleophilic ring closure is described.
Synthesis of the taxol AB-system by olefination of an A-ring C1 ketone and direct B-ring closure
作者:David Crich、Swaminathan Natarajan、Joyce Z Crich
DOI:10.1016/s0040-4020(97)00411-0
日期:1997.5
Two syntheses of 13-deoxy-taxol C1 ketones are presented. Olefination of these C1 ketones is achieved, indirectly, via either the Meyer-Schuster reaction or by introduction of a vinyl group with vinylcerium dichloride followed by allylicrearrangement. Both methods provide the E-olefin exclusively. Dihydroxylation of these olefins is achieved with catalytic OsO4 and NMNO in moderate yield, providing