Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact:

Price: ¥ 4,400 (Yen only)
Period: This Article can be accessed for 7 days.

Communication | Regular issue | Vol 24, No. 3, 1986, pp.601-605
Published online, 1st January, 1970
DOI: 10.3987/R-1986-03-0601
Protosappanin B, a New Dibenzoxocin Derivative from Sappan lignum

Masahiro Nagai* and Seiji Nagumo

*Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan


A new dibenzoxocin derivative, named protosappanin B, C16H16O6, white amorphous powder, [α]D15 -11.4° (MeOH) was isolated from the heart-wood of Caesalpinia sappan L. (Leguminosae). It yielded a trimethyl ether (2) on methylation with diazomethane, a tetraacetate (5) and a pentaacetate (6) on acetylation, and sappanin (4) on alkali fusion. Protosappanin B (1) was chemically correlated with trimethyl ether (3) of protosappanin A (7). On the basis of the chemical and spectroscopic evidence, the chemical structure of 1 was established as 3,7,10,11-tetrahydroxy-7,8-dihydro-7(6H)-dibenz[b,d]oxocinmethanol. The cd spectrum of 1 indicated that its biphenyl system preferentially takes S configuration, from which S configuration was tentatively assigned to C-7 of 1.