Intervenolin analogs with a phenyl substituent at the 2- or 3-position were synthesized. The compounds (3-11) showed weak or no inhibitory activity toward the growth of MKN-74 gastric adenocarcinoma cells, even in the presence or absence of the corresponding Hs738 stromal cells, whereas 2-substituted analogs exhibited selective anti-Helicobacterpylori activity. Introduction of a pendant side chain