Synthesis and Antibacterial Activities of Novel 2,5-Diphenylindolo[2,3-e] Pyrazolo[1',5':3",4"]pyrimido[2",1"-c] [1,2,4]triazines

Abstract

The formation of (E)-3-{2-(2,5-diphenylpyrazolo[1,5-c]pyrimidin-7-yl)hydrazono}indolin-2-ones 3 has been achieved by condensation of equimolar amounts of 7-hydrazino-2,5-diphenylpyrazolo[1,5-c]pyrimidine (1) and isatin (or isatin derivatives) 2at room temperature. The (E)-products could be isomerized into corresponding the (Z)-3 isomers. Reactions of the latter fused heterocyclic hydrazones towards different electro-philic reagents yielded the corresponding 3-substituted derivatives 4–7. Dehydrative cyclisation of the hydrazones 3 using phosphorus oxychloride afforded the 2,5-diphenyl- indolo[2,3-e]pyrazolo[1',5':3",4"]pyrimido[2",1"-c][1,2,4] triazines 13. The polyfused heterocyclic ring system 13 underwent electrophilic substitution reactions at position 4 rather than at position 3. The 3-bromo isomer of 17 was prepared by a sequence of reactions starting from 2,5-diphenylpyrazolo[1,5-c]pyrimidine-7(6H)-thione (11). The orientation of the electrophilic attack was supported by spectroscopic and chemical evidence. Some of the synthesized compounds were found to possess slight to moderate activity against the microorganisms Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa.

Novel synthesis of Some Novel Pyrimidine Heterocycles.

“…Importance of pyrimidine in the medical field as therapeutic agents is well known [1][2][3][4]; also, it is used for the synthesis of a wide variety of bioactive azines [5][6][7][8]. Fused pyrimidines are among those azines which are found to exhibit many pharmacological activities such as antimicrobial [9,10] anti-inflammatory [11], anticancer [12], analgesic, anticonvulsant [13], antidiabetic [14], antioxidant [15], and antiviral [16] activity. In continuation of our efforts aimed to synthesize of fused azines derivatives [17,18]; we report herein about the utilization of thiopyrimidine derivative 1 for the construction of some novel annulated pyrimidines with expected biological activity.…”

Nonionic Surfactants as Potential Carriers of a Synthesized Pyrimidine Derivative: Spectroscopic and Quantum Chemical Investigations

“…Pyrimidine is the structural unit of DNA and RNA, which plays a vital role in various existence progressions and the most abundant pyrimidine is uracil, cytosine and thymine. Besides these, anthracene moiety have also a remarkable range of biological activity mainly as antibacterial agents, antitumor, and antifungal compounds. Abd‐El‐Aziz et al reported that anthracene derivatives are also known for their [4+4] cycloaddition reactions as well as excimer generation and suggested the formation of the anthracene excimer with an emission at 510 nm …”

Synthesis, Spectroscopic Studies of Fluorinated Pyrimido‐1,2,4‐Triazines: Protective Effect Against Some Plant Pathogenic Fungi

“…Pyrimidines continue to receive much attention in recent years due to their unique physical, chemical, and pharmacological applications as potential microbial growth inhibitors [1][2][3], photochemical probe agents [4], and biocidal agents [5]. A variety of nitrogen-bridged pyrimidines was reported to be used as multi-targeted small molecule inhibitors and resistance-modifying agents [6][7][8][9][10][11]. On the other hand, 1,2,4-triazines and their condensed hetrobicyclic ring systems have attracted considerable interest in recent years as anti-HIV [12], antifungal agents [13,14], molluscicidal agents [15], and antitumor agents [16].…”