Synthesis of some new propanamide derivatives bearing 4- piperidinyl-1,3,4-oxadiazole, and their evaluation as promising anticancer agents

Purpose: To sequentially synthesize piperidine-4-carboxylic acid ethyl ester-appended 1,3,4-oxadiazole hybrids and to evaluate them as anticancer agents.Methods: Ethyl 1-[(4-methylphenyl)sulfonyl]-4-piperidinecarboxylate (1) was synthesized from 4- methylbenzenesulfonylchloride (a) and ethyl 4-piperidinecarboxylate (b). Compound (1) was converted into ethyl 1-[(4-methylphenyl)sulfonyl]-4-piperidine carbohydrazides (2) and 5-{1-[(4- methylphenyl)sulfonyl]-4-piperidinyl}-1,3,4-oxadiazole-2-thiol (3) respectively. A variety of aryl amine (4a-l) were treated with 2-bromopropionylbromide to synthesize an array of propanamide (5a-l). Finally, 5-{1-[(4-methylphenyl)sulfonyl]-4-piperidinyl}-1,3,4-oxadiazole-2-thiol (3) and propanamides (5a-l) were reacted to synthesize target compounds (6a-l). Purity compounds 6a-l was confirmed by spectroscopic techniques like (1H-NMR), (13C-NMR) and EI-MS. To determine their anticancer potential, the change in absorbance of mixture and cell line before and after incubation was determined.Results: All the compounds 6a-l were successfully synthesized in 73-85 % yield. Compounds 6h, 6j and 6e have low IC50 (±SD) values of 20.12 ± 6.20, 10.84 ± 4.2 and 24.57 ± 1.62 μM to act as strong anticancer agents relative to doxorubicin (0.92 ± 0.1 μM) used as a reference.Conclusion: The synthesized propanamide derivatives bearing 4-piperidinyl-1,3,4-oxadiazole are potential anticancer agents, but further studies, especially in vivo, are required to ascertain their therapeutic usefulness.Keywords: Ethyl isonipecotate, Propanamides, 1,3,4-Oxadiazole, Anti-cancer activit

Deletion of Genes Implicated in Protecting the Integrity of Male Germ Cells Has Differential Effects on the Incidence of DNA Breaks and Germ Cell Loss

Infertility affects approximately 20% of couples in Europe and in 50% of cases the problem lies with the male partner. The impact of damaged DNA originating in the male germ line on infertility is poorly understood but may increase miscarriage. Mouse models allow us to investigate how deficiencies in DNA repair/damage response pathways impact on formation and function of male germ cells. We have investigated mice with deletions of ERCC1 (excision repair cross-complementing gene 1), MSH2 (MutS homolog 2, involved in mismatch repair pathway), and p53 (tumour suppressor gene implicated in elimination of germ cells with DNA damage).We demonstrate for the first time that depletion of ERCC1 or p53 from germ cells results in an increased incidence of unrepaired DNA breaks in pachytene spermatocytes and increased numbers of caspase-3 positive (apoptotic) germ cells. Sertoli cell-only tubules were detected in testes from mice lacking expression of ERCC1 or MSH2 but not p53. The number of sperm recovered from epididymes was significantly reduced in mice lacking testicular ERCC1 and 40% of sperm contained DNA breaks whereas the numbers of sperm were not different to controls in adult Msh2 -/- or p53 -/- mice nor did they have significantly compromised DNA.These data have demonstrated that deletion of Ercc1, Msh2 and p53 can have differential but overlapping affects on germ cell function and sperm production. These findings increase our understanding of the ways in which gene mutations can have an impact on male fertility