Rabdosia diterpenoids from

Recent Advances in the Chemistry of Diterpenoids from Rabdosia species... 

Various biological activities, such as antibacterial and antitumor ones, and inhibitory activities as to insect growth and oxidative phosphorylation in rat mitochondria, are known for Rabdosia diterpenoids [2]. During the past decade, the antitumor activity of diterpenoids isolated from R. trichocarpa [149. 150]... 

The present volume reflects these developments, and there is a growing emphasis on bioactive natural products. Articles in this volume include those on structure-activity relationships of highly sweet natural products, chemical constituents of cchinodenns, diterpenoids from Rabdosia and Eremophila sp., structural studies on saponins, marine sesquiterpene quinoncs and antimicrobial activity of amphibian venoms. The reviews on bioactive metabolites of Phomopsis, cardenolide detection by ELISA, xenocoumacins and bioactive dihydroisocoumarins, CD studies of carbohydrate-molybdate complexes, oncogene function inhibitors from microbial secondary metabolites and Gelsemium and Lupin alkaloids present frontier developments in several areas of natural product chemistry. It is hoped that the present volume, which contains articles by eminent authorities in each field, will be received with the same enthusiasm as the previous volumes of this series. 

Oxidation patterns of ring D in Rabdosia diterpenoids derived from ent-16-kaurene are classified into 5 types shown in Table VI. Each class exhibits characteristic spectral data, from which the structural features of ring D are easily deduced. Table VI shows typical UV, IR, and NMR data for a typical example belonging to each class. 

Fujita, T, Y Takeda, T. Shingu, and A. Ueno Structures of Effusanins, Antibacterial Diterpenoids from Rabdosia effusa. Chemistry Letters 1980, 1635. 

Takeda, Y, T. Fujita, and C.-C. Chen Structures of Lasiocarpanin, Rabdolasional, and Carpalasionin New Diterpenoids from Rabdosia lasiocarpa. Chemistry Letters 1982, 833. 

Fujita, T., Y. Takeda, and T. Shingu Longikaurin A and B New, Biologically Active Diterpenoids from Rabdosia longituba. Chem. Commun. 1980, 205. 

Ochi, M., M. Okamura, H. Kotsuki, 1. Miura, I. Kubo, and T. Kubota Bitter Diterpenoids from Rabdosia shikokiana (Makino) Hara. Bull. Chem. Soc. Japan 55,2208 (1982). 

Node, M., N. Ito, K. Fuji, and E. Fujita Three New 8,9-seco-e r-Kaurane Diterpenoids from Rabdosia shikokiana (Labiatae). Chem. Pharm. Bull. (Japan) 30,2639 (1982). 

Takeda, Y., T. Fujita, and A. Ueno A New Diterpenoid from Rabdosia umbrosa var. latifolia. Abstract Paper of the 21st Chugoku-Shikoku Regional Meeting of Pharmaceutical Society of Japan, p. 53 (1982). 

Fujita,T.,Y.Takeda, H.-D. Sun, Y. Minami,T. Marunaka, S.Takeda, Y. Yamada, and T. Togo Structures and Antitumor Activity of Diterpenoids from Rabdosia (Labiatae) Plants. Abstract papers of 4th Symposium on the Development and Application of Naturally Occurring Drug Materials (Japan), p. 34 (1982). 

Table V lists those Rabdosia species which have been investigated in alphabetical order and the diterpenoids isolated from each species.

The distribution of diterpenoids in five Rabdosia umbrosus varieties has been investigated from the chemotaxonomic point of view 96) R. umbrosa var. umbrosa, R. umbrosus var. hakusanensis, R. umbrosus var. latifolia, R. umbrosus var. excisinflexa, and R. umbrosus f. kameba were studied by reverse phase HPLC (97) and six of the known /-kaurene type diterpenoids, kamebakaurinin, isodomedin, umbrosinA, mebadonin, kamebakaurin, and kamebanin were recognized. Kamebanin was found in all... 

Sun, H., J. Chao, Z. Lin, T. Marunaka, Y. Minami, and T. Fujita The Structure of Rubescensin C A New Minor Diterpenoid isolated from Rabdosia rubescens. Chem. Pharm. Bull. (Japan) 30, 341 (1982). 

Node, M., M. Sai, E. Fujita, and K. Fuji Structure of New Diterpenoids, Trichorabdals E, F, and G from Rabdosia trichocarpa. Abstract papers of the 27th Symposium on the Chemistry of Terpenes, Essential Oils, and Aromatics (Japan), p. 70... 

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