Biological active principles

Techniques in isolation and structure elucidation of (volatile) semiochemicals from beetles are the same as in other insects. Problems are mainly due to the often very small amounts of target compounds, embedded in large amounts of non-active substances which form a kind of cosmetic formulation for the biologically active principle. Comprehensive reviews of analytical approaches have been published [18-20]. 

Quinazolines have become increasingly important as biologically active principles, e.g., as antiseptics or antimalarials. An interesting approach to this class consists of a combination of the aza-Wittig reaction with photochemical processes, as shown in Scheme 76. o-Azidocinnamates (206) are cyclized with the aid of triethyl phosphite to afford 2-alkoxyquinolines... 

The isolation of the allomonal factor of L. hlrsutum was relatively straightforward and unremarkable as this factor was typical of many organic molecules in its solubility properties and was not apparently prone to thermal, photolytic or oxidative degradation. The biologically active principle could be removed from the leaf surface with a chloroform wash and could be selectively removed from unwanted pigments and waxes by redlssolvlng... 

Reactions and interconversion of norditerpenoid dilactones, biologically active principles isolated from Podocarpus nagi. Hayashi, Y. Matsumoto, M. J. Org. Chem. 1982,47,3421-3428. 

B-84M1 722-01 N. J. Leonard in Biologically Active Principles of Natural Products, eds. W. Voelter and... 

Advances in research are performed on the genus Astragalus and about 100 different species have been chemically studied imtill now [249]. The genus appears highly uniform from a chemical point of view, with three kinds of biologically active principles and three diffent groups of toxic compounds. The active constituents are saponins, flavonoids, and polysaccharides, while nitro-compoimds, indolizidine alkaloids and the seleniferous derivatives are included in the poisonous groups. 

More specifically, antifungal sesquiterpene dialdehydes from the Warburgia trees are reviewed based on our own study. These sesquiterpene dialdehydes are the rare phytochemicals that exhibited potent antifungal activity against C. albicans. The aim of this review is to describe an example of what can be done after identification of biologically active principles. 

With the aim of search for biologically active principles of having preventive and therapeutic effects for ethanol intoxication from Chinese traditional medicines, Aralia elata Seem, was investigated by Yoshikawa et al. Elatosides A-D were isolated and elucidated from fresh bark. 

Yamahara, J., H. Mibu, T. Sawada, et al. 1981. Biologically active principles of cmde dmgs. Antidiabetic principles of Comi fmctus in experimental diabetes induced by streptozotocin. Yakugaku Zasshi 101(l) 86-90. 

Field cultivation of Ginseng is laborious and requires more than four years and special precautions to avoid direct sunshine and infection. Also, because of soil depletion, Ginseng cannot be cultivated on the same plot for at least 10 —15 years. Hence tissue culture of this medicinal plant has been attempted by several groups in Japan, Korea, U.S.A. and China as a means for producing biologically active principles on a manufacturing scale. 

Shibata S 1981 Chinese drug constituents isolation of the biologically active principles. In Natori S, Ikekawa N, Suzuki M (eds) Advances in natural products chemistry. Kodansha Tokyo, 398-416... 

Yamahara J, Kobayashi M, Saiki T, Sawada T et al. 1983 Biologically active principles of crude drugs. Pharmacological evaluation of cholagogue substances in clove and its properties. J Pharm Dyn 6 281-286... 

Yamahara J, Matsuda H, Watanabe H, Sawada T et al. 1980 Biologically active principles of crude drugs. Analgesic and anti-inflammatory effects of Keigai Schizonepeta tenuifolia Briq.). Yakugaku Zasshi 100 713-717... 

Yamahara J, Mibu H, Sawada T, Fujimura H et al. 1981 Biologically active principles of crude drugs. Antidiabetic principles of Corni fructus in experimental diabetes induced by strep-tozotocin. Yakugaku Zasshi 101 86-90... 

In its simplest embodiment, a nanovector comprises the particle and the biologically active principle it carries (Figure 11.13a). Experience with particulates, such as liposomes, has shown that nanovectors of dimensions between 10 and 1000 nm are cleared very rapidly from the bloodstream by means of uptake by phagocytic cells of the RES [117]. In order to decrease the clearance time, and thereby allow... 

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