A FORMAL TOTAL SYNTHESIS OF (-METHYL TRACHYLOBAN-18-OATE AND (+)-METHYL 16-OXO-17-NORKAURAN-18-OATE - REGIOSELECTIVE AND DIASTEREOSELECTIVEPREPARATION OF METHYL (13S)-13-HYDROXYISOATISIREN-18-OATE FROM (-)-ABIETIC ACID())

Authors
BERETTONI M DECHIARA G IACOANGELI T LOSURDO P BETTOLO RM DIMIRABELLO LM NICOLINI L SCARPELLI R
Citation
M. Berettoni et al., A FORMAL TOTAL SYNTHESIS OF (-METHYL TRACHYLOBAN-18-OATE AND (+)-METHYL 16-OXO-17-NORKAURAN-18-OATE - REGIOSELECTIVE AND DIASTEREOSELECTIVEPREPARATION OF METHYL (13S)-13-HYDROXYISOATISIREN-18-OATE FROM (-)-ABIETIC ACID()), Helvetica Chimica Acta, 79(7), 1996, pp. 2035-2041
Citations number
35
Categorie Soggetti
Chemistry
Journal title
Helvetica Chimica Acta → ACNP
ISSN journal
0018019X
Volume
79
Issue
7
Year of publication
1996
Pages
2035 - 2041
Database
ISI
SICI code
0018-019X(1996)79:7<2035:AFTSO(>2.0.ZU;2-2
Abstract
A novel preparation of methyl (13S)-13-hydroxyisoatisiren-18-oate (4), a key-intermediate in a synthesis of (+)-methyl trachyloban-18-oate ( (+)-1), from (-)-abietic acid, is described. Since (-)-1 has been prev iously convened into (-)-methyl 16-oxo-17-norkauran-18-oate ((-)-16), our preparation of 4 constitutes also a formal total synthesis, from ( -)-abietic acid, of (+)-16. Key steps in this approach were the allene photoaddition to podocarp-8(14)-en-13-one (5) and the conversion of t he endo-toluene-4-sulfonate 11 into the exo-benzoate 12b.