A Convenient Synthesis of Bis-(dihydro)caffeoylspermidines

Caffeoyl spermidines are valuable alkaloids naturally existing in many plant species. These alkaloids are characterized as pharmacologically important ingredients of many plant extracts used in traditional medicines. Bis-caffeoylspermidine and bis-dihydrocaffeoylspermidine exhibit antioxidant, anti-inflammatory, and enzyme inhibition properties that make them valuable natural sources of safer therapeutic agents. However, the limited availability of these compounds in nature derives the attention of synthetic chemists. Therefore, we synthesized bis-caffeoylspermidine and bisdihydrocaffeoylspermidine using cheaper and commercially available starting materials in 97% and 86% overall yields, respectively. The synthetic scheme can be upgraded to the commercial-scale synthesis of these compounds.