Kaurene derivatives

Aralia chinensis L. A. cordata Thunb. var. continentalis (Kitag.) Y. C. Chu A. elata (Miq.) Seem. A. elata (Miq.) Seem. F. subinermis Y. C. Chu Jia Mu, Du Huo (Aralia) (root) Diterpenoids such as (-) pimaradene, (-) kaurene derivatives, l-pimara-8, 15-dien-19-oic acid, aralosides, araligenin, oleanolic acid, beta-taralin, alpha-taralin.20 48 50 Carminative, for arthralgia, gastroenteritis, headache, diuretic, antidiabetic, antiseptic. 

Hasson, E.P., West, C.A. "Properties of the system for the mixed function oxidation of kaurene and kaurene derivatives in microsomes of the immature seed of Mar ah macrocarpus. Cofactor requirements." Plant Physiol., 1976, 58 473- 78. 

ENRIQUEZ, R,G., MIRANDA, C,E., ORTIZ B LEON, I., MAGOS, G., PENA, A., REYNOLDS, W,F., GNECCO, D., The unambiguous detection of kaurenic derivatives in aqueous infusions of Montanoa tomentosa by GC-MS and 2D-NMR spectroscopy An answer to contradictory reports., Planta Med., 1996,62,569-571. 

The partial synthesis from epicandicandiol of some C- and H-labelled kaurene derivatives has been described.These have possible application in the study of the biosynthesis of the Isodon diterpenoids. The syntheses of [17- C]kaur-16-en-20-ol from enmein and of 3-oxygenated derivatives of [17- C]kaur-16-ene from ent-3jS,19-dihydroxy-kaur-16-ene have also been described. The synthesis of radioactive aphidicolin has also been reported. It has been shown ° that ent-kaur-15-ene is formed by the dwarf mutant (ds) of maize in place of ent-kaur-16-ene. 

Concerning the development of "zoapatle" as a contraceptive phytomedicine, limited attempts have been made to systematically demonstrate the presence of the different classes of compounds in the traditional decoction. So far, reports are conclusive only about the presence of kaurenic derivatives, kauradienoic acid, kaurenoic acid and monoginoic acid [45] and the oxepane tomexanthin [39]. Progress in analytical methods allows one today to carry out a complete HPLC profile of an aqueous plant extract. Thus, "zoapatle s" decoction should be analyzed again, using the 40 plus isolated compounds as standards. 

To discover whether 7-oxygenated c t-kaurene derivatives are potential precursors of enmein and oridonin, the 17-labeled 7-oxygenated kaurenes (200,201 a, 202, and 203) were prepared (127) and administered to growing plants. The results showed that 7-oxygenated kaurenes as well as 15-oxo-kaurene (195) are potential precursors of Rabdosia diterpenes (128). 

Kubo, L, I. Ganjian, andT. Kubota Chemotaxonomic Significance of /-Kaurene Derivatives in Rabdosia umbrosus YsLnQtiQS. Phytochemistry 21, 81 (1982). 

Four basic skeletal types of kaurene-derived diteipene alkaloids are known the atisine, heteratisine, lycoctonine, and veatchine types. 

Bohlmann F, Ngoleva N 1977 Naturally occurring terpene derivatives. 97. New kaurene derivatives from Wedelia species. Phytochemistry 16 579-581... 

Bohlmann, F., J. Jakupovic, A. Schuster, R.M. King, and H. Robinson New melampolides, kaurene derivatives and other constituents from Ichthyothere species. Phytochem. 21, 2317 (1982). 

Lequesne, P.W., V. Honkan, K.D. Onan, P.A. Morrow, and D. Tonkyn Oxidized kaurene derivatives from leaves of Solidago missouriensis and S, rigida, Phytochem. 24, 1785 (1985). 

Pakrashi, S.C., P.P. Ghosh Dastidar, and E. Ali Newer (-)-kaurene derivatives from Enhydra fluctuans Lour. Indian J. Chem. 9, 84 (1971). 

Alternatively, some of the natural kaurenes may function as free radical scavengers against oxidative stress. These compounds are amenable to photooxidation in the presence of photosensitizers under moderate UV light to give allylic alcohol derivatives via the corresponding hydroperoxides 50 and 51 (Banerjee et al., 1973). This reaction may explain at least in part the synthesis in vivo of various hydroxyl kaurenes naturally found in Espeletiinae and other plant groups. 

The molecular geometries of lanosterol (28 ) and kaurene (29 ) were derived from the X-ray crystal structures. In the case of kaurene, the co-ordinates of hydrogen atoms were generated using ACACS system and optimized by the MNDO calculations. 

Biosynthesis (Chapter 6).— E>etailed studies have been reported with individual enzymes responsible for the early stages of terpenoid biosynthesis. The mechanism whereby two molecules of famesyl pyrophosphate couple to furnish squalene is still uncertain and the structure of the C30 pyrophosphate intermediate isolated by Rilling in 1966 remains elusive. The genesis of the monoterpenoid portion of the indole alkaloids has been intensively studied. Of special interest was the discovery of the bismonoterpenoid foliamenthin, which is a derivative of the indole alkaloid precursor secologanin. The biosynthesis of the gibberellins has received detailed attention on both sides of the Atlantic. nr-kaurene, the parent, is formed via geranylgeranyl pyrophosphate and enr-copalyl pyrophosphate and this seems to follow a... 

Kauranes and Gibberellic Acids.— The parent tetracyclic diterpene from which the gibberellic acids are derived, is enf-kaurene (62). Several workers have... 

Details of the conversion of enmein into ( — )-kaurene have been described. The hemi-acetal (67), produced by an acyloin condensation of enmein derivatives,... 

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. 

Diterpenes related to e r-kaurene (5p,10a-configuration). Other Structural Types Derived from the enr-Kaurane Skeleton Gibberellins Grayanotoxins... 

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