Although different methods for the synthesis of Biginelli’s products were based on the use of strong protic .. Pyrimidine and its derivatives. A Mini Review: Biginelli Reaction for the Synthesis of Dihydropyrimidinones. Conference Pyrimidine Containing Derivatives Scheme 7. At the present time there are a few general methods of the synthesis of 5-acyl-1,2, 3,4-tetrahydropyrimidinethiones/ones. One of them is the Biginelli reaction.
|Published (Last):||27 October 2004|
|PDF File Size:||3.67 Mb|
|ePub File Size:||4.37 Mb|
|Price:||Free* [*Free Regsitration Required]|
In 1 H NMR spectra, all of the products showed a singlet peak at about 5. Mohana Roopan and R. The latter data stimulate our interest to investigate the reactivity of C5 ester towards hydrazine hydrate under solvent-free conditions which produce three different ring cleavage products.
Articles from Iranian Journal of Pharmaceutical Research: Experimental Melting points were determined with an Electrothermal digital apparatus and were uncorrected.
Normal saline was used for preparation of inoculants having turbidity equal to 0.
View at Google Scholar M. The 13 C NMR spectra of these compounds showed a signal at about Melting points were measured with a Stuart melting point apparatus and were uncorrected. Abstract Certain Biginelli pyrimidines with ester substitution in C5 were subjected to unexpected ring opening upon solvent-free reaction with hydrazine hydrate to give three products: The reported reactions of hydrazine hydrate with pyrimidines 7a —7 c and 9a —9 c.
In the light of previous data and in continuation of our interest in the chemistry of biginekli hydrate towards certain heterocycles [ 44 — 48 ], we aim herein to study the solvent-free reaction of hydrazine hydrate on C5 ester Biginelli pyrimidines 4a — 4h Figure 3. An improved synthesis of Biginelli-type compounds via phase-transfer catalyst.
With respect to R 4the reaction works best with aromatic aldehydes [ 31 ]. Syntyesis scheme begins with rate determining nucleophilic addition by the urea to the aldehyde.
Introduction Tetrahydroprymidines and their derivatives have recently attracted considerable interest thanks to their pharmacological activities such as bigine,li 1antiviral 2calcium channel modulation 3 and antibacterial activity 4 – 6. The solvent control was included, although no antibacterial activity has been noted. Open in a separate window.
Antibacterial activities of compounds 1- 4, 6 and 8- 10 were measured on three gram negative bacteria E.
Ghabbour3,4 Maha M. Support for anN-Acyliminium Ion Intermediate1″. The synthetic pathway for preparation of tetrahydropyrimidine derivatives Interestingly, the reported findings revealed that the hydrazinolysis of pyrimidine-2 1 H -one 7a4-methylpyrimidin-2 1 H -one 7bor 4,6-dimethylpyrimidin-2 1 H -one 7c resulted in the formation of 1 H -pyrazole 8a3-methyl-1 H -pyrazole 8b and 3,5-dimethyl-1 H -pyrazole 8crespectively, in addition to urea 1a in each case Figure 2 [ 40 ].
The straight forward synthesis of DHPMs resulted in the discovery of many important agents such as calcium channel modulators, adrenergic receptor antagonists, and mitotic kinesin inhibitors, in addition to anticancer, anti-inflammatory, antimicrobial, and antioxidant activities [ 9 — 13 ]. The Biginelli Condensation Revisited”. The broad absorption band for stretching vibration of NH groups was detected in the region cm The remaining solid was filtered, washed with water and ethanol and it was consequently dried and recrystallized using ethanol.
The authors would like to extend their sincere appreciation to the Deanship of Scientific Research at King Saud University for its funding of this research through the Research Group, Project no.
Cephalexin was used as the standard. View at Google Scholar C. Said1 Wagdy M. Dimethyl sulfoxide DMSO only, control for compounds and references. On the other hand, when R 5 is an ester group, free carboxylic acids can be produced [ 32 — 34 ].
This final step ensues a second condensation and results synhhesis the Biginelli compound. Each concentration was repeated 4 times for each of the bacteria and the average results of inhibitory effects are illustrated in Table 1. Melting points were determined with an Electrothermal digital apparatus and were uncorrected.
There was a problem providing the content you requested
To the best of our knowledge, there are no reports concerned with the accessibility of C6 for the nucleophilic reaction by hydrazine hydrate. The reaction synthewis C5 esters with thiosemicarbazide, in acetone, to afford thiosemicarbazones 6 is reported Figure 1 [ 39 ]. To receive news and publication updates for Journal of Chemistry, enter your email address in the box below. Iran J Pharm Res. The obtained solid product 16a — 16d was filtered, crystallized from ethanol, and finally dried.
This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Synthesis and evaluation of some new fluorinated hydroquinazoline derivatives as antifungal agents.
Retrieved from ” https: Michaels, Antibiotics Annualvol. Table of Contents Alerts.
Synthesis of Some New Tetrahydropyrimidine Derivatives as Possible Antibacterial Agents
Atul Kumar has reported first enzymatic synthesis for Biginelli reaction via yeast catalysed protocol in pyrimidinw yields. Synthesis of some novel chromenopyrimidine derivatives and evaluation of their biological activities. The structure of 3,4-dihydropyrimidinones DHPMs 4anticancer agent Monastrol, hydrazide 5, and thiosemicarbazone 6. The reaction mixture was allowed to cool and poured on crushed ice.
Kabil5 Nasser Biginekli. These facts showed the reactivity of sp 2 C6 of pyrimidines towards hydrazine hydrate and, subsequently, the ring opening of pyrimidine moiety.
A mixture of DHPMs 4a — 4h 0.