Premium
Synthetic Anthracyclinones, XXXI. Total Synthesis of Racemic ϵe‐Rhodomycinones via Keto‐Ester Cyclization
Author(s) -
Krohn Karsten,
Priyono Wahyudi
Publication year - 1986
Publication title -
liebigs annalen der chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0170-2041
DOI - 10.1002/jlac.198619860902
Subject(s) - chemistry , regioselectivity , hydroxylation , stereoselectivity , alkylation , stereochemistry , lithium (medication) , pyridine , cleavage (geology) , medicinal chemistry , organic chemistry , catalysis , enzyme , medicine , geotechnical engineering , fracture (geology) , engineering , endocrinology
The keto esters 15 – 17b were prepared by regioselective alkylation of the anthraquinone acetals 12 – 14 followed by cleavage of the acetals and methyl ethers and esterification. The tetracyclic trans ‐β‐hydroxy esters 25 – 27b were formed predominantly upon treatment of 15 – 17b with Triton B in pyridine, whereas lithium amides in THF gave only the cis ‐hydroxy esters 28 and 29a . Stereoselective hydroxylation of 25 – 27b afforded the rhodomycinones 38 – 40a and 6 of natural configuration ( cis ‐2,4‐diols), while that of 28 – 30b gave the not naturally occurring trans ‐2,4‐diols 41 – 43b .