To find podophyllotoxin compounds with superior bioactivitiy and less toxicity, a series of novel conjugates of ring-A-modified 4-epipodophyllotoxin and stavudine with amino acids as spacers were synthesized, i.e., the N-[(2'.3'-didehydro-3'-deoxythymidin-5'-O-yl)carbonyl]-substituted L-amino acid rel- (3aR,4S,9R,9aR)-13,3a,4,9,9a-hexahydro-6,7-dimethoxy-1-oxo-9-(3,4,5-trimethoxyphenyl)naphtho[2,3-c]furan-4-yl esters 8a-8f.