Lipophilic cations: Synthesis, analysis and screening of aryl phosphonium salt esters

CHED 270

Lisa Chin, LCHIN_6097@RIC.EDU and John C. Williams Jr., jcwilliams@ric.edu. Physical Sciences Department, Rhode Island College, 600 Mt. Pleasant Ave., Providence, RI 02908
Arylphosphonium salts are attracted to the mitochondria of malignant cells, due to the charge gradient, thus making them potential anti-cancer agents. Some compounds bind DNA in vitro. In molecular mechanics calculations they exhibit intercalation, electrostatic interactions, and minor groove binding. Others are neither active in vitro nor show binding in silico.We prepared alkyl esters of these salts three steps with good yield for screening against bacteria, cell lines and DNA. Triphenylphosphine and alpha-bromo-para-toluic acid are heated with toluene to precipitate salts. These were chlorinated by heating in neat thionyl chloride, and esterified by reaction with an alcohol in the same vessel. After precipitation in diethyl ether, the solid is isolated and vacuum dried. Melting point, IR, NMR, UV-VIS, HPLC, and LC/MS are used to verify structures.