Synthesis and antimicrobial activity of new substituted dihydropyrimidine derivatives

A new series of ethyl 6-methyl-4-[substituted]phenyl-2-[substituted]-phenacyl-thio-1, 4- dihydropyrimidine-5-carboxylate [2a-x] was prepared by reaction of ethyl 1, 2, 3, 4-tetrahydro-6-methyl-4-[substituted]phenyl-2-thioxopyrimidine-5-carboxy-late J [a-d] with phenacyl bromides. Compounds 1[a-d] were synthesized using the principle of Bignelli condensation by one pot reaction of the appropriate araldehyde. ethyl acetoacetate and thiourea in acidic medium. Confirmation of the chemical structure of the synthesized compounds [2a-x] was substintiated by different spectral data IR. [1]H-NMR. MS in addition to their microanalyses. The newly synthesized compounds were evaluated for their antimicrobial activities. The antibacterial and antifungal testing identified compounds 2b, 2e, 2k, 21, 2m, 2n, 20, 2p, 2q, 2, and 2x as the most effective agents in comparison to Chloramphenicol and Clotrimazole as reference antibacterial and antifungal drugs respectively

Synthesis of some new 1,4-disubstituted piperazine-2,3-dione derivatives of potential anthelmintic activity

The purpose of this study based upon design and synthesis of a new series of 1,4-disubstituted piperazine-2,3-dione derivatives through two steps reaction. This protocol involves the formation of N,N/-Bis-[4-substituted benzyl]-ethane-1,2-diamine and N,N/-Bis-[1-[4-substituted phenyl]-ethyl]-ethane-1,2-diamine derivatives [1a-i] through reductive alkylation reaction from ethylenediamine and different carbonyl compounds in the presence of sodium cyanoborohydride. The second step involves reaction of compounds [1a-i] with diethyl oxalate affording the target compounds. Consequently, nine new 1,4-disubstituted piperazine-2,3-dione derivatives were synthesized as the target compounds, 1,4-Bis-[4-substituted benzyl]-piperazine-2,3-dione and 1,4-Bis-[1-[4-substituted phenyl]-ethyl]-piperazine-2,3-dione derivatives [2a-i]. The structures of the target compounds were elucidated depending upon the data of the different spectral as well as the elemental methods of analysis. In addition, a mass spectrum, for a representative example, was carried out where the expected fragmentation pattern is in accordance with the structure of the considered compound. The lipophilicity of the target compounds as expressed from the ClogP and the measured Rf remarkably supercede that of piperazine. The preliminary anthelmintic activity of the newly synthesized derivatives [2a-i] was investigated in vitro against Enterobiuos vermicularis and Fasciola hepatica. The tested compounds exhibited, in all cases, considerable inhibitory effects on the growth of the tested parasites in comparison with piperazine hydrate as a reference drug

Synthesis and antitubercular activity of some mannich bases derived from isatin isonicotinic acid hydrazone

The purpose of this study based on the design and synthesis of a new series of 4-[1-[substitutedaminomethyl]]-2-oxo-2,3-dihydro-1H-3-indolylidene-pyridine- carboxylic acid hydrazones [2a-g] in a trial to overcome the resistance developed with the therapeutic uses of isonicotinic acid hydrazide [isoniazid, INH]. The new compounds were prepared by reacting isatin isonicotinic acid hydrazone with formalin and the appropriate secondary amines. The structures of the newly synthesized compounds were elucidated using different spectral data [IR, 1 HNMR, and 13 CNMR] as well as elemental methods of analyses. The lipophilicity of the synthesized compounds supercedes that of INH as expressed by Clog P.The new compounds [2a-g] as well as INH as a reference drug were tested for their antitubercular activity against bovine Mycobacterium tuberculosis at a dose level of 10 micromol. The tested compounds exhibited comparable inhibitory activity against the tested TB strain comparing to INH a reference drug