C(21)−C(40) of Tetrafibricin via Metal Catalysis: Beyond Stoichiometric Chiral Reagents, Auxiliaries, and Premetalated Nucleophiles
摘要:
The C(21)-C(40) fragment of fibrinogen receptor inhibitor tetrafibricin was prepared in 12 steps from propane diol (longest linear sequence). In this approach, 6 C-C bonds are formed via asymmetric iridium catalyzed transfer hydrogenative carbonyl allylation and 2 C=C bonds are formed via Grubbs olefin cross-metathesis.
Total synthesis of (+)-phorboxazole A, a potent cytostatic agent from the sponge Phorbas sp.
作者:Gerald Pattenden、Miguel A. González、Paul B. Little、David S. Millan、Alleyn T. Plowright、James A. Tornos、Tao Ye
DOI:10.1039/b308305e
日期:——
A convergent total synthesis of phorboxazole A (1a), from the C(3-19), C(20-27) and C(33-46) fragments 5, 4 and 91, respectively, concentrating on stereocontrolled formation of the bonds at C(2-3), C(19-20) and C(27-28), is described. Although a coupling reaction between a macrolide ketone and the side chain substituted sulfone, at C(27-28) was not successful, a Wadsworth-Emmons olefination involving
Synthetic studies towards phorboxazole A. A convergent synthesis of the C31C46 polyene oxane-hemiacetal side chain
作者:Gerald Pattenden、Alleyn T Plowright、James A Tornos、Tao Ye
DOI:10.1016/s0040-4039(98)01258-1
日期:1998.8
A convergent and stereoselective synthesis of the C31-C46 side chain unit in the marine natural product phorboxazole A, which accommodates five asymmetric centres, three carbon-to-carbon double bonds and an oxane-hemiacetal unit, is described. (C) 1998 Elsevier Science Ltd. All rights reserved.