The alkylation reaction of guanine and N-acetylguanine with model compounds such as isopropyl bromide or 4-heptyl tosylate were studied. The reaction conditions such as temperature, solvent, base, and catalyst were ex...The alkylation reaction of guanine and N-acetylguanine with model compounds such as isopropyl bromide or 4-heptyl tosylate were studied. The reaction conditions such as temperature, solvent, base, and catalyst were examined for their effects on the reaction rate, and the yield and regioselectivity of the coupling reaction. The highest yield was obtained by using DMSO as the solvent. The reaction proceeded in a homogenous manner to give higher yield of 9-N and 7-N substituted product in a mole ratio of 1:1. The ratio could be raised to 2:1 if dibenzo-18-crown-6 was used as a catalyst. Using the above procedure, three carba-DHPG analogues bearing different 1'-C alkyl side chains were synthesized.展开更多
A new and efficient method for the synthesis of potential antiviral agents Carba-ACV (3) and Carba-DHPG (4) is described. The synthesis makes the use of N- acetylguanine to condense with the corresponding tosylates (1...A new and efficient method for the synthesis of potential antiviral agents Carba-ACV (3) and Carba-DHPG (4) is described. The synthesis makes the use of N- acetylguanine to condense with the corresponding tosylates (16) and (11) under the catalysis of dibenzo-18-C-6, resulting in the desired coupling products (17) and (12) in good yield and in the case of Carba-DHPG with high regioselecti- vity.展开更多
文摘The alkylation reaction of guanine and N-acetylguanine with model compounds such as isopropyl bromide or 4-heptyl tosylate were studied. The reaction conditions such as temperature, solvent, base, and catalyst were examined for their effects on the reaction rate, and the yield and regioselectivity of the coupling reaction. The highest yield was obtained by using DMSO as the solvent. The reaction proceeded in a homogenous manner to give higher yield of 9-N and 7-N substituted product in a mole ratio of 1:1. The ratio could be raised to 2:1 if dibenzo-18-crown-6 was used as a catalyst. Using the above procedure, three carba-DHPG analogues bearing different 1'-C alkyl side chains were synthesized.
文摘A new and efficient method for the synthesis of potential antiviral agents Carba-ACV (3) and Carba-DHPG (4) is described. The synthesis makes the use of N- acetylguanine to condense with the corresponding tosylates (16) and (11) under the catalysis of dibenzo-18-C-6, resulting in the desired coupling products (17) and (12) in good yield and in the case of Carba-DHPG with high regioselecti- vity.