Biological Activity of Quinazoline Alkaloids and Their Analogs

Biological Activity of Quinazoline Alkaloids and Their Analogs 

The fact that several quinazoline alkaloids and the plants containing such types of alkaloids show a variety of biological activities has spurred the preparation and pharmacological and biological evaluation of a great number of quinazoline derivatives. Intensive research in the quinazoline field is still in progress. This topic has been reviewed by Amin etal. 173), Gupta etal. 174), Johne 175,176), Siisse and Johne 177), and by Yakhontov et al. 178). 

Vasicinone (29), the autooxidation product of vasicine, produces definite bronchodilatation against histamine-induced bronchospasm, slight hypotension, and a positive inotropic action with increased coronary flow 152,156,183,185). Prakash et al. 140) postulated that the combination of sympathomimetic amines and vasicinone in some Sida species would account for their major therapeutic uses in the Indian system of medicine, for example, in the treatment of asthma and other chest ailments. Vasicinone has been used as a model for the development of the expectorant 2-amino-3,5-dibromo-jV-cyclohexyTV-methylbenzene-methanamine. 

7-Hydroxypeganine (30) produces transient hypotension in cats, contraction of isolated guinea pig intestine, and depression of isolated guinea pig heart, all of which can be blocked by atropine. It also produces slight contraction of isolated 

Although the claims made for the biological activity of vasicine and vasicinone are controversial, some analogs of both alkaloids have been synthesized. 

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VII. Biological Activity of Quinazoline Alkaloids and Their Analogs... 

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