Aspongdopamines A
and B (1 and 2), unusual
adducts composed of N-acetyldopamine and adenine
were isolated from the insect Aspongopus chinensis. Compounds 1 and 2 are positional isomers
both isolated as racemates. Chiral separation assisted by 14-step
total synthesis and computation including vibrational circular dichroism
calculations allowed us to unambiguously assign the absolute configurations
of eight stereoisomers. Renal fibrosis inhibition of the stereoisomers
was evaluated in TGF-β1-induced rat kidney epithelial cells.