Ratchanok PingaewSupaluk PrachayasittikulSomsak RuchirawatVirapong PrachayasittikulSrinakharinwirot UniversityMahidol UniversityChulabhorn Research InstituteChulabhorn Graduate Institute2018-10-192018-10-192013-01-01Medicinal Chemistry Research. Vol.22, No.1 (2013), 267-27715548120105425232-s2.0-84872013061https://repository.li.mahidol.ac.th/handle/20.500.14594/31565The modified Pictet-Spengler reaction of phenylethylbenzene sulfonamide with a commercially available glyoxal to construct 1-benzoyl- and 1-acetyl-1,2,3,4-tetrahydroisoquinolines 9a-n has been reported. The reaction could be accomplished, regardless of the oxygenation pattern on the aromatic ring, leading to the N-sulfonyltetrahydroisoquinoline analogs which are versatile intermediates for the synthesis of new thiosemicarbazone analogs of 1,2,3,4-tetrahydroisoquinoline. Bioactivity test revealed that most thiosemicarbazones displayed cytotoxic potency against MOLT-3 cell lines with an IC50less than 20 μg/mL. Significantly, the thiosemicarbazone analog of 1-acetyltetrahydroisoquinoline 9j was the most potent cytotoxic compound against HuCCA-1, HepG2, and MOLT-3 cells. This study provides the novel lead molecules for further development. © 2012 Springer Science+Business Media, LLC.Mahidol UniversityChemistryPharmacology, Toxicology and PharmaceuticsArticleSCOPUS10.1007/s00044-012-0025-y