Synthesis of wiedendiol-A and wiedendiol-B from labdane diterpenes

Synthesis of 11,12-Epoxydrim-8,12-en-11-ol, 11,12-Diacetoxydrimane, and Warburganal from (−)-Sclareol

“…The pure compound was isolated as a colorless oil after eluting with diethyl ether through a silicagel column. 13 C NMR data were identical to those assigned in the literature for 2, which was described as a mixture with the dialdehyde 11. 9 The 1 H NMR spectra of solutions of 2 in CDCl 3 , which were kept overnight, showed the appearance of aldehyde protons at δ 9.86 (d, J ) 1.2 Hz) and 10.12 (s), due to the formation of 11.…”

Studies on Naturalp-Terphenyls: Total Syntheses of Vialinin A and Terrestrin B

“…Ortholithiation (2.4 eq. of n-BuLi, TMEDA, À78-0 C) of 18 and subsequent treatment with triisopropylborate and an oxidative work-up resulted in partial debenzylation, 24) giving no hydroquinone derivative. On the other hand, the reaction with 19 under similar conditions proceeded smoothly to afford desired hydroquinone 20 in a high yield.…”

A Facile Approach toward 8-O-4'-Neolignans: Synthesis of Threo-7',8'-Dihydromachilin D through Jacobsen Epoxidation

“…Compound 6 was submitted to benzylation by nucleophilic substitution of benzyl bromide under three previously reported conditions (Table 1). In spite of potassium carbonate have been reported as common use base in benzylation (Gu et al, 2000;Barrero et al, 1998;Buchi et al, 1967), it was not able to accomplish successfully the reaction on 6 (entry 1, Table 1). The addition of molecular sieve together with temperature increasing was not efficient either.…”