Synthesis, Crystal Structure and Antitumor Activity of 6,7,8-Trimethoxy-1-(4-methoxy-3-nitrophenyl)-4-(pyridin-4-ylmethyl)-3,4-dihydroisoquinoline

A novel class of 3,4-dihydroisoquinolines (7a similar to e) was designed, synthesized and characterized by IR, NMR and ESI-MS. The crystal structure of compound 7a (6,7,8-trimethoxy-1-(4-methoxy-3-nitrophenyl)-4-(pyridin-4-methyl)-3,4-dihydroisoquinoline, C25H25N3O6, M-r = 463.48) was determined by X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P2(1)/n with a = 12.074(5), b = 12.896(6), c = 15.450(7) angstrom, beta = 105.846(5)degrees, V = 2314.4(17) angstrom(3), Z = 4, D-c = 1.330 Mg/m(3), mu(MoK alpha) = 0.096 mm(-1), F(000) = 976, S = 0.991, the final R = 0.0467 and wR = 0.1231 for 4545 unique reflections (R-int = 0.0656) with 3117 observed ones. The bioassay showed that compounds 7a similar to e exhibit moderate antitumor activities in vitro.