Isolation and structural elucidation of new saframycins Y3, Yd-1, Yd-2, Ad-1, Y2b and Y2b-d.

Isolation and structural elucidation of new saframycins Y3, Yd-1, Yd-2, Ad-1, Y2b and Y2b-d.

A new series of saframycins Y3, Yd-1, Yd-2, Ad-1, Y2b and Y2b-d was produced by directed biosynthesis employing resting cells of saframycin producer, Streptomyces lavendulae No. 314. Their structures were determined by comparison with the spectral data of UV, IR, and 1H and 13C NMR of saframycin A, whose structure has already been established. Saframycin Y3 is 25-deoxy-25-aminosaframycin A, whi...

Nsttute for Research on Pover 1 Yd

pursuant to the provisions of the Economic Opportunity Act of 1964. The author is grateful to David L. Featherman for helpful comments on an earlier draft and to Arthur S. Goldberger for helpful discussions at several stages, but neither colleague necessarily agrees with any part of the current version. ABSTRACT The book under review deals with modelS which identify and measure factors determin...

NSTTUTE F R . RESEARCH ON POVER 1 YD , scWK

ISOLATION AND STRUCTURAL ELUCIDATION OF THE FIRST KNOWN C-HOMOPROTOBERBERINE

A novel C-homoprotoberberine alkaloid, Hediamine (2), has been isolated from the roots of Berberis actinucantha (Berberidaceae). Conclusive proof for the structure of hediamine was obtained by its comparison with the isomeric lactam (4), by chemical transformation, and by means of spectroscopic techniques (UV, IR, MS, NMR).

Crystal Structure of the Superconducting Layered Cobaltate Na X Coo 2 ·yd 2 O Crystal Structure of the Superconducting Layered Cobaltate Na X Coo 2 ·yd 2 O

We have used electron diffraction and neutron powder diffraction to elucidate the structural properties of superconducting Na x CoO 2 ·yD 2 O over a wide compositional range. Our measurements show that superconducting samples exhibit a number of supercells ranging from 1 3 a * to 1 15 a * , but the predominant modulation, observed also in the neutron data, is a double hexagonal cell with dimens...