Judith Polonsky

Roquefortine and isofumigaclavine A, metabolites fromPenicillium roqueforti

The structures of two metabolites fromPenicillium roqueforti, designated roquefortine and isofumigaclavine A, have been determined by chemical and spectroscopic studies.

Isolation and structure (X-ray analysis) of marcfortine A, a new alkaloid from Penicillium roqueforti

The structure of marcfortine A, a novel alkaloid isolated from Penicillium roqueforti, has been established by X-ray analysis; two minor alkaloids, marcfortine B and C, as well as the previously known roquefortine have also been isolated.

Structures of marcfortine B and C (X-ray analysis), alkaloids from

Resume Marcfortine B and C are minor alkaloids isolated from the mycelium of Penicillium roqueforti . The structure of marcfortine B was established by spectral means and that of marcfortine C by X-ray diffraction analysis.

Activity of quassinoids as antifeedants against aphids

A series of quassinoids was tested for antifeedant activity against the aphidMyzus persicae (Hemiptera, Aphididae). Isobrucein B, brucein B and C, glaucarubinone, and quassin decreased feeding at concentrations down to 0.05% and isobrucein A was effective at 0.01%. Only quassin showed no phytotoxic effects and is therefore the most promising compound for further development.

Structural requirements of quassinoids for the inhibition of cell transformation

Abstract The effects of eleven quassinoids on Rous sarcoma virus induced cell transformation and on growth of normal cells were examined. At concentrations of 0.15-1 μg/ml they inhibited foci formation (76–99 %) without toxic effects on normal cells. The most active compounds also affected virus production by transformed cells. In intact normal and transformed cells, protein and DNA synthesis was equally affected after 3 hours of exposure to quassinoids of both cell types. RNA synthesis was not inhibited. This study has shown that the structural requirement of a C-15 ester in the quassinoids for antileukemic activity in vitro and in vivo is not essential for their antitransforming activity.

The structure of amoorastatone and the cytotoxic limonoid 12-hydroxyamoorastatin

2 new limonoid-type terpenes have been isolated from an aqueous extract of seeds produced by the Eastern Himalayan (India) plantAphanamixis grandifolia Bl. By interpreting principally mass spectral and nuclear magnetic resonance data, the structures of 12-hydroxyamoorastatin (2b) and amoorastatone (3) were elucidated. Unequivocal evidence for the 12-hydroxyamoorastatin structural assignment was obtained by chemical conversion to sendanin (4). Amoorastatin derivative2b was found to significantly inhibit growth of the murine P388 lymphocytic leukemia cell lines but amoorastatone in the same system was inactive. In a comparative biological study, sendanin (4) and anthothecol (7) were also found significantly to inhibit growth of the P388 cell line, while rohitukin (8) and limonin (9) were found to be inactive.

Antifeedant activity of quassinoids

The antifeedant activity of 13 quassinoids of different structural types has been studied against the Mexican bean beetle (Epilachna varivestis Mulsant) 4th instar larvae and the southern armyworm (Spodoptera eridania Crawer) 5th instar larvae. All quassinoids tested displayed significant activity against the Mexican bean beetle and, thus, do not reveal a simple structure-activity relationship. Five quassinoids were active against the southern armyworm. Interestingly, four of these-bruceantin (I), glaucarubinone (VI), isobruceine A (VIII), and simalikalactone D (XI)-possess the required structural features for antineoplastic activity. The noncytotoxic quassin (X) is an exception; it is active against both pests.

The isolation and structure of 13,18-dehydroglaucarubinone, a new antineoplastic quassinoid from Simarouba amara.

An investigation of the Guyana plantSimarouba amara Aubl. (Simaroubaceae) for antineoplastic quassinoids led to isolation and structural determination of the new quassinoids 2′-acetylglaucarubine (1a) and 13,18-dehydroglaucarubinone (2). The previously known 2′-acetylglaucarubinone (3a) and glaucarubinone (3b) were also obtained. The new quassinoid2 was found significantly to inhibit growth of the murine lymphocytic leukemia P388.

Isolation and structure (x-ray analysis) of karinolide, a new quassinoid from Simaba Multiflora ☆

Karinolide is a structurally novel C20 quassinoid isolated from the French Guyanan Simaroubaceae, Simaba multiflora A.Juss. whose structure was established by X-ray diffraction analysis. 6α-Senecioyloxychaparrin , the known 6α-senecioloyxychaparrinone and 9-methoxycanthin-6-one were also isolated ; their structure were determined by spectral means.

Isolation and structure of sergeolide, a potent cytotoxic quassinoid from Picrolemma pseudocoffea

Abstract Sergeolide 2 , isolated from the French Guyanan Simaroubaceae, Picrolemma pseudocoffea Ducke, is a novel quassinoid possessing the normal C20 basic skeleton with a butenolide function attached to the A ring. Structure 2 was established by interpretation of the 400 MHz 1H-NMR and the 13C-NMR data. It is highly cytotoxic and is active against mouse leukemia P388. The previously known isobruceine B 1 was also isolated.