Synthesis, Crystal Structure and Antitumor Activities of 1,2,3,4-Tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) Derivatives

A novel and efficient Ir-catalyzed 1,4-and 1,2-addition of diphenylphosphine oxide to quinolines was developed to obtain various 1,2,3,4-tetrahydroquinoline-2,4-diyl（bisdiphenylphosphine oxide） derivatives. The structures of these derivatives were characterized by H-RMS and NMR analysis. X-ray crystallography showed that 3 a is in a monoclinic system, space group of P21/c with a = 13.0464（16）, b = 12.6244（16）, c = 20.210（3） ?, β = 105.215（2）o, V =3211.9（7） ?3, Z = 4, F（000） = 1352, μ = 0.42 mm–1, S = 1.07, the final R = 0.059 and wR = 0.195.The in vitro antitumor activities of target compounds were evaluated by MTT assay against human cancer K562, HL-60, HeLa and BGC-823. The target compounds demonstrated weak or moderate antitumor activity against these cell lines.