title: Synthesis and anti-tumor activity of alkenyl camptothecin esters.
abstract: OBJECTIVE
  To study the degrees of influence of changing side ester chains at position C20 of camptothecin on the anti-tumor activity of the molecules.
  
  
  METHODS
  The esterification reaction of camptothecin 1 and 9-nitrocamptothecin 2 with crotonic anhydride in pyridine gave the corresponding esters 3 and 4, respectively. The acylation of 1 and 2 with cinnamoyl chloride gave products 7 and 8. Epoxidation reaction of 3 and 4 with m-chloroperoxybenzoic acid in benzene solvent gave the products 5 and 6. Esters 3, 4, and 5 were tested for anti-tumor activity against 14 human cancer cell lines.
  
  
  RESULTS
  Both in vitro and in vivo anti-tumor activity studies for these esters were conducted and the data demonstrated positive results, that is, these esters were active against the tested tumor lines.
  
  
  CONCLUSIONS
  Alkenyl esters 3 and 4 showed strong anti-tumor activity in vitro against 14 different cancer cell lines. Ester 3 was active against human breast carcinoma in mice and the toxicity of the agent was not observed in mice during the treatment, implying that this agent is effective for treatment with low toxicity.
authors.affiliation: Stehlin Foundation for Cancer Research and St Joseph Hospital Cancer Laboratory, 1918 Chenevert Street, Houston, Texas 77003, USA. zcao@stehlin.org
authors.forename: Zhi-Song
authors.initials: ZS
authors.lastname: Cao
authors.forename: John
authors.initials: J
authors.lastname: Mendoza
authors.forename: Albert
authors.initials: A
authors.lastname: Dejesus
authors.forename: Beppino
authors.initials: B
authors.lastname: Giovanella
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000473:pathology; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor / Q000187:drug effects; D004952:Esters / Q000737:chemistry; D006801:Humans; D020128:Inhibitory Concentration 50; D051379:Mice; D015394:Molecular Structure; D009368:Neoplasm Transplantation
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004952:Esters; C079905:rubitecan; D002166:Camptothecin