Antineoplastic agents. 536. New sources of naturally occurring cancer cell growth inhibitors from marine organisms, terrestrial plants, and microorganisms(1a,).

Bioassay-guided fractionation of extracts of various plants, marine organisms, and microorganisms has led to the discovery of new natural sources of a number of known compounds that have significant biological activity. The isolation of interesting and valuable cancer cell growth inhibitors including majusculamide C ( 1), axinastatin 5 ( 5), bengazoles A ( 6), B ( 7), and E ( 8), manzamine A ( 10), jaspamide ( 11), and neoechinulin A ( 19) has been summarized.

Lignans from Dendrobium chrysanthum.

A new neolignan glucoside denchyside B along with three known lignans have been isolated from the herbs of Dendrobium chrysanthum Wall. (Orchidaceae). The structures were elucidated on the basis of spectroscopic methods.

New fluorenone and phenanthrene derivatives from Dendrobium chrysanthum.

Two new fluorenone derivatives denchrysans A (1) and B (2) and one new phenanthrenediglycoside denchryside A (3) were isolated from the herbs of Dendrobium chrysanthum (Orchidaceae). Their structures were established on the basis of spectral evidence.

Influence of substrate salinity on structure characteristics of petiole vessel elements of Bruguiera gymnorrhiza.

The anatomy of the mature leaf's petioles of one-year-old Bruguiera gymnorrhiza seedlings cultured in greenhouse was studied in this paper. The results are as follows: (1) Most of the vessel elements of the petioles of B. gymnorrhiza are of scalariform. Helical vessels and their transition type only account for a small portion of the total vessels. However, there is a notable increase in the number of helical vessels and their transition type with increasing salinity. (2) The length of petioles, diameter and length of scalariform vessel elements, and bar number of a scalariform perforation plate all exhibit of parabolic relationship with substrate salinity. They maximized at salinity between 20 g/L and 30 g/L. (3) It is new phenomenon that there are two scalariform perforation plates, facing differently, at the polar of the vessel element of the petioles in the seedlings under 10 g/L treatment. (4) Under low salinity, the changes in the structure of vessel elements had the tendency to promote the transportation of water with increasing salinity. While under high salinity, it tended to raise the reliability of the water transportation. The adaptive significance of the morphological characteristics of vessel elements in the petiole was discussed.