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Three new tetrasaccharide glycosides, differing from one reported previously in the type of short-chain fatty acids ester-linked to the tetrasaccharide core, have been isolated and identified from an oligosaccharide fraction of Ipomea stans. Preliminary screening tests showed that the fraction containing these compounds had pronounced cytotoxicity towards three human tumor cell lines as well as specific antibiotic activity against two bacterial strains.

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The effect of an alcoholic extract of seeds of Casimiroa edulis on blood pressure and heart rate was determined in rats anesthetized with pentobarbital and compared with that of histamine. The extract induced hypotension, accompanied at high doses by tachycardia. Hypotension after histamine was more transient and was not accompanied by changes in heart rate. Experiments with a variety of autonomic antagonists revealed that extract-induced hypotension was not mediated by histamine H2, muscarinic, or beta-adrenergic receptors, but involved an H1 mechanism. After H1 blockade, the depressor response was reversed to a pressor effect, mediated by alpha-adrenoceptor stimulation. The increase in heart rate was due in part to H1 and in part to beta-adrenergic receptor activation. It was suggested that imidazole derivatives could be responsible for the depressor effect observed. The pressor response could be caused by these or other components of the extract.