856889-90-2Relevant academic research and scientific papers
Synthesis of 7,9-dideoxybaccatin IV analogs from sinenxan A
Zhang, Meng,Yin, Dali,Guo, Ji-Yu,Liang, Xiao-Tian
, p. 5519 - 5527 (2007/10/03)
Sinenxan A, a taxoid isolated from callus tissue cultures of Taxus yunnanensis was converted into 13-oxo-7,9-dideoxy-2-debenzoyl-2-acetyl-baccatin IV and 7,9-dideoxy-2-debenzoyl-4-deacetyl-baccatin IV, a key framework of 1,7,9-trideoxypaclitaxel. Several special steps in this transformation are worthy of note: (1) deoxygenation by treatment with hypophosphorous acid at C-14 position; (2) a highly regioselective O-deacetylation of taxanes at C-5 position; and (3) stereoselective reduction of the 13-carbonyl group by transannular assistance from the C-4-hydroxyl.
