[Caffeoylquinic acid derivatives from leaves of Lonicera japonica].

OBJECTIVE: To study the caffeoylquinic acid derivatives from the leaves of Lonicera japonica. METHOD: The compounds were isolated by column chromatography and identified on the basis of physico-chemical constants and spectral analysis. RESULT: Five caffeoylquinic acid derivatives were isolated,and their structures were identified as 3,4-di-O-caffeoyl quinic acid methyl ester (1), 5-O-caffeoyl quinic acid methyl ester (2), 3,4-di-O-caffeoyl quinic acid (3), 1,3-di-O-caffeoyl quinic acid (4) and chlorogenic acid (5), respectively. CONCLUSION: Compounds 2, 4 were obtained from this genus for the first time. Compounds 1, 3 were obtained from this plant for the first time.