تحضير مشتقات جديدة للسيفالسبورين == Synthesis of New Cephalosporin Derivatives
Author name:
ابتهال قحطان عبد الله
Supervisor name:
رضا ابراهيم حسين البياتي | شاكر محمد علوان العقيدي
General topic:
Chemistry
Specific topic:
Chemistry
Degree:
Doctorate
University:
Mustansiriyah University - College Of Science
Language:
English
University location:
Baghdad
First pages:
25T1699 - p.pdf
Abstract:
A novel series of cephalosporins were designed, synthesized, and tested as antimicrobial agents. These cephalosporins include the following : - 7 - [2 - (6 - aryl - 5 - arylamino - 5,6 - dihydro imidazo [2,1 - b] - 1,3,4 - thiadiazole - 2 - yl) - Dithioacetamido] - Desacetoxy cephalosporanic acid derivatives (59e - 63e). 7 - [2 - (6 - aryl - 5 - arylamino - 5,6 - dihydro imidazo [2,1 - b] - 1, 3, 4 - thiadiazole - 2 - yl) - thio acetamido] - Desacetoxy cephalosporinic acid derivatives (59g - 63g). 7 - [2 - (6 - arylidene amino) - 1, 3, 4 - thiadiazole - 5 - yl) - Dithio acetamido] - Desacetoxy cephalosporinic acid derivatives (59k - 63k). 7 - [2 - (6 - arylidene amino) - 1,3,4 - thiadiazole - 5 - yl) - thio acetamido] - Desacetoxy cephalosporinic acid derivatives (59n - 63n).These cephalosporins were prepared by using 7 - Amino desacetoxy cephalosporanic acid (7 - ADCA) with different acyl side chain. Some of these novel cephalosporins contain fused - ring system derived from fusion of the thiadiazole nucleus with imidazole and disulfide or sulfide band compounds [59e - g, 63e - g]. Other novel cephalosporins were prepared containing Schiff’s bases of thiadiazole with different substituted benzaledyhyde and disulfide or sulfide band as in compounds [59k, n - 63k, n]. The preparation of such compounds involved several chemical processes, such as Schiff’s bases, ring closure, thiol - disulfide interchanges, S - alkylation and acylation through mixed anhydride method.The identification and analysis of most of the prepared compounds and novel cephalsporins were achieved using I.R spectroscopy, U.V spectroscopy and elemental analysis, and ΄HNMR spectroscopy of some of these cephalosporin derivatives.The antimicrobial activities of these cephalosporin derivatives were screened using representative strains of gram - negative and gram - positive bacteria. Most of the prepared cephalosporins showed reasonable antimicrobial potency compared to cephalexine. However, the cephalosporins containing a fused ring system with disulfide band showed a broader spectrum and were more active than the others.
