Chemical modification of plant alkaloids. I. Aminomethylation of barbituric acid derivatives by cytisine
摘要:
Reaction of cytisine with 1-mono- and 1,3-disubstituted 5-arylmethylbarbituric acids in the presence of formaldehyde results in aminomethylation of C-5 to form the corresponding 5-cytisylmethylbarbituric acids. The structures of the products are found using PMR spectroscopy mid mass spectrometry. 1-Phenyl-5-(2,4-dimethoxybenzyl)-5-cytisylmethylbarbituric acid is obtained as a mixture of two steroisomers in an approximately 2:1 ratio.
Twenty-four derivatives of N,N-dimethylbarbituric acid 1-24 were screened for their DPPH radical scavenging activity. These compounds showed an excellent antioxidant activity. A structure-activity relationship has been discussed, while all the synthetic compounds were characterized by spectroscopic techniques and elemental analysis.