NMR spectroscopy analysis was introduced to investigate the weak interaction of four 5'—mononucleotides with tryptamide and leucinamide. Assuming a 1∶1 complex formation, the association constants were determine...NMR spectroscopy analysis was introduced to investigate the weak interaction of four 5'—mononucleotides with tryptamide and leucinamide. Assuming a 1∶1 complex formation, the association constants were determined by nonlinear regression analysis. The association affinity of 4 mononucleotides with tryptamide decreased in the order: G>A>C>U, indicating that purine bases stack more strongly with tryptamide than pyrimidine bases. But with leucinamide the affinity decreases in the order: G>C>A=U, suggesting an amino acid—anticodonic preferential interaction. The implication of the present data to the origin of genetic code was briefly discussed.展开更多
The bacillamide 1 is a new algaecide from the marine bacterium Bacillus sp. SY-1. Its analogues bacillamide 3 and alkaloid 4 were firstly synthesized effectively from D-alanine. The key step was a coupling reaction vi...The bacillamide 1 is a new algaecide from the marine bacterium Bacillus sp. SY-1. Its analogues bacillamide 3 and alkaloid 4 were firstly synthesized effectively from D-alanine. The key step was a coupling reaction via the mixed anhydride. All structures were confirmed by IH NMR and 13C NMR. The final compounds were confirmed by 1H NMR, 13C NMR and HRMS and the results are consistent with the reported natural products.展开更多
文摘NMR spectroscopy analysis was introduced to investigate the weak interaction of four 5'—mononucleotides with tryptamide and leucinamide. Assuming a 1∶1 complex formation, the association constants were determined by nonlinear regression analysis. The association affinity of 4 mononucleotides with tryptamide decreased in the order: G>A>C>U, indicating that purine bases stack more strongly with tryptamide than pyrimidine bases. But with leucinamide the affinity decreases in the order: G>C>A=U, suggesting an amino acid—anticodonic preferential interaction. The implication of the present data to the origin of genetic code was briefly discussed.
基金the National Science Foundation of China(Nos.20421202,and 20572055) for financial support
文摘The bacillamide 1 is a new algaecide from the marine bacterium Bacillus sp. SY-1. Its analogues bacillamide 3 and alkaloid 4 were firstly synthesized effectively from D-alanine. The key step was a coupling reaction via the mixed anhydride. All structures were confirmed by IH NMR and 13C NMR. The final compounds were confirmed by 1H NMR, 13C NMR and HRMS and the results are consistent with the reported natural products.
