title: Heterocyclic ring extension of estrone: synthesis and cytotoxicity of fused pyran, pyrimidine and thiazole derivatives.
abstract: The one pot reaction of estrone with the aromatic aldehydes 2a-c and either of malononitrile or ethyl cyanoacetate afforded the fused pyran derivatives 4a-f. On the other hand, carrying the same reaction using thiourea instead of the cyanomethylene reagent gave the fused pyrimidine derivatives 6a-c. The latter compounds reacted with phenacyl bromide to give the thiazolo[3,2-a]pyrimidine derivatives 8a-c. The reaction of the title compound with bromine gave the monobromo derivative 13 which in turn reacted with either thiourea or cyanothioacetamide to give the thiazole derivatives 14 and 16, respectively. The cytotoxicity of the newly synthesized products was evaluated against six human cancer and normal cell lines where the results showed that compounds 4c, 4f, 6b, 8b, 8c, 10, 13, 16, 18c and 19c exhibited optimal cytotoxic effect against the cancer cell lines, with IC50's in the nM range.
authors.affiliation: Department of Chemistry, Faculty of Science, Cairo University, Giza, A.R., Egypt. Electronic address: raafat_mohareb@yahoo.com.
authors.forename: Rafat M
authors.initials: RM
authors.lastname: Mohareb
authors.affiliation: Department of Chemistry, Kuwait University, P.O. Box 5969, 13060 Safat, Kuwait.
authors.forename: Fatima
authors.initials: F
authors.lastname: Al-Omran
authors.affiliation: Department of Chemistry, Faculty of Science, Helwan University, Cairo, A.R., Egypt.
authors.forename: Rasha A
authors.initials: RA
authors.lastname: Azzam
mesh_terms: D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D004970:Estrone / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D013058:Mass Spectrometry; D066244:Proton Magnetic Resonance Spectroscopy; D011714:Pyrans / Q000737:chemistry; D011743:Pyrimidines / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry
chemical_list: D006571:Heterocyclic Compounds; D011714:Pyrans; D011743:Pyrimidines; D013844:Thiazoles; D004970:Estrone
keywords: Cytotoxicity; Estrone; Pyran; Pyrimidine; Thiazole