10.22376/ijpbs.2019.10.1.p1-12 Volume 2 Issue 4 2011 (October - December) From QSAR studies, a series of salicylaldehyde semicarbazones, HOC lessThan sub greaterThan 6 lessThan /sub greaterThan H lessThan sub greaterThan 4 lessThan /sub greaterThan CH=N‑NHCONR lessThan sub greaterThan 2 lessThan /sub greaterThan (H lessThan sub greaterThan 2 lessThan /sub greaterThan R lessThan sub greaterThan 2 lessThan /sub greaterThan ) and their Cu(II) complexes were synthesized, characterized and investigated for their biological activities previously. Results obtained showed that one of the most active compounds in this series is [Cu(HBnz lessThan sub greaterThan 2 lessThan /sub greaterThan )Cl]. Thus, in this study, research was then carried out to investigate the anti-tumour property of this compound. The LD lessThan sub greaterThan 50 lessThan /sub greaterThan of [Cu(HBnz lessThan sub greaterThan 2 lessThan /sub greaterThan )Cl] was determined to be at 75 mg/kg. Anti-tumour property was observed when this compound was introduced to tumours of human origin (MOLT-4 on SCID mice) and murine origin (3LL on normal mice). Peter Peng Foo Lee And Kenneth K Poon Salicylaldehye semicarbazone, copper(II) complexes, antitumour, in vivo, LD50. 174-190