1-Hydroxytaxinine (1)isacytotoxic taxane diterpenoid. Its central eight-membered B-ring possesses four oxygenfunctionalizedc enters (C1, C2, C9, and C10) and two quaternary carbon centers (C8 and C15), and is fused with six-membered A-and C-rings.The densely functionalizedand intricately fused structure of 1 makes it ah ighly challenging synthetic target. Reported here is an efficient radical-based strategy for assembling 1 from A-and C-ring fragments.T he A-ring bearing an a-alkoxyacyl telluride moiety underwent intermolecular coupling with the C-ring fragment by aE t 3 B/ O 2 -promoted decarbonylative radical formation. After construction of the C8-quaternary stereocenter,apinacol coupling reaction using alow-valent titanium reagent formed the B-ring with stereoselective installation of the C1,C2-diol. Subsequent manipulations at the A-and C-rings furnished 1 in 26 total steps.

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Terpenes U 0200 Synthesis and Absolute Configuration of Brevione B, an Allelochemical Isolated from Penicillium sp. -(TAKIKAWA*, H.; IMAMURA, Y.; SASAKI, M.; Tetrahedron 62 (2006) 1, 39-48; Dep. Biosyst. Sci., Grad. Sch. Sci. Technol., Kobe Univ., Nada, Kobe 657, Japan; Eng.) -Nuesgen 21-177

Taxol is a clinically used drug for the treatment of various types of cancers. Its 6/8/6/4‐membered ring (ABCD‐ring) system is substituted by eight oxygen functional groups and flanked by four acyl groups, including a β‐amino acid side chain. Here we report a 34‐step total synthesis of this unusually oxygenated and intricately fused structure. Inter‐ and intramolecular radical coupling reactions connected the A‐ and C‐ring fragments and cyclized the B‐ring, respectively. Functional groups of the A‐ and C‐rings were then efficiently decorated by employing newly developed chemo‐, regio‐, and stereoselective reactions. Finally, construction of the D‐ring and conjugation with the β‐amino acid delivered taxol. The powerful coupling reactions and functional group manipulations implemented in the present synthesis provide new valuable information for designing multistep target‐oriented syntheses of diverse bioactive natural products.