Design,Synthesis And In Vitro Antitumor Assay Of Benzoyl/Phenylacetyl Hydroxamic Acids As HDACs Inhibitors

Abnormal balance between acetylation and deacetylation of intracellular histone regulated by histone acetylase(HATs)and histone deacetylases(HDACs)leads to the high level of deacetylated histone,compact structure of nucleosome,expression retardation of the inhibitory factor related to cell cycle or tumor inhibition,high expression of the factor related to tumor formation,and eventually oncogenesis.The specific inhibition to HDACs of HDACi results in the normal level of acetylated histone,the upexpression of antioncogene,introduction of differentiation and apoptosis of tumor cell,and proliferation inhibition of tumor cell.N-phenyl/replaced phenyl-4-benzoyl/phenylacetylamino-phenylhydroxamicacids designed by the replacement via phenyl/replaed phenyl of hydrogen of 4-benzoyl/phenylacetylamino-phenylhydroxamic acid that was given by esterification of 4-nitrobenzoic acid as the starting material,reduction of nitryl,benzoylation/phenylacetylation of the reducted amino group,esterolysis,and acylation of phenylhydroxylamine/replaced phenylhydroxylamine preparated by reduction of nitrobene/replaced nitrobene in the present of catalyst Raneys nickel,and was confirmed by 1HNMR,13CNMR and HRMS,was expected to strengthen the hydrophobic interaction between phenyl/replaed phenyl and 14A hydrophobic cavity in the bottom of HDAC,to fasten with HDACs,to decrease acidity of hydroxamic acid,and to remove the unwanted effect.The inhibition of proliferation of A549.HeLa,HepG2,Ec-109,and HFF cell lines and HDACs by MTT method and drug-screening kit with synthesized 4-benzoyl/phenylacetylamino-phenylhydroxamic acids as the negtive control and vorinostat(SAHA)as a positive control of the target compounds was determined.The potent target compounds after the preliminary screen were performed via Annexin V/FITC double staining kit and PI cell cycle flow cytometry kit for the influence of apoptosis introduction and cyclic blockage in HepG2 cell line.The activity-screening experiment shown that HDACs inhibition of 9d,9f,15d,and 15f(IC50<3μM)was more than the one of SAHA;proliferation inhibition of 9d,15c,and 15d(IC50<300p,M)was more effective than the one of SAHA in A549 cell line;9d,9e,15d,and 15f(IC50<410μM)more than SAHA in HeLa cell line;9a,9d,9f,15d,and 15f(IC50<490μM)more than SAHA in HepG2 cell line;15c and 15d(IC50<470μM)more than SAHA in Ec-109 cell line;but 9a,9d,9f,15d,and 15f(IC50>>600μM)much weaker than SAHA in HFF cell line.9d,9f,15d,and 15f induced HepG2 apoptosis more substantially than SAHA.And 9f,15d,and 15f arrested S phase of HepG2.The whole in vitro activity-screening experiments suggested that proliferation inhibition in cancer cell lines of substituted 4-acetylamino-phenylhydroxamic acids was more effective than the one of the unsubstituted,such as 16,17 were hardly valid;electron-donating groups in position 4’ of phenyl in 4-acetylamino-phenyl-hydrox-amic acids more than the ones in position 2’ or 3 ’ of phenyl,such as 9d,15d,and 15f more than SAHA;chlorine in position 4 ’ of phenyl in N-phenyl-4-benzoyl/phenyl-acetylamino-\phenylhydroxamic acids actively more excellent than methyl,which chlorine in position 4’ of phenyl was profit for the hydrobolic interaction with 14A hydrophobic cavity in the bottom of HDAC;phenylacetylization of N-phenyl-4-amino-phenylhydroxamic acids more than benzoylization,such as 15f was significantly more than 9f.So this study discovered a novel HDACi of N-aromatic substituted 4-phenylacetylamino-phenylhydroxamic acids,in which 15d and 15f might serve as prospective novel HDACis due to proliferation inhibition of them in cancer cell lines dramatically more effective more than the one of SAHA.