O. M. O. Habib

Novel quinazolinone derivatives: synthesis and antimicrobial activity

Abstract4-(4-Oxo-4H-3,1-benzoxazin-2-yl)phenyl-4-methylbenzenesulfonate (2) was prepared and reacted with some primary aromatic amines, e.g., aniline, p-chloro aniline, p-methoxy aniline, p-amino benzoic acid and p-amino acetophenone. It reacted also with some heterocyclic amines, e.g., 2-aminothiazole, 2-aminobenzothiazole, 5-amino-4-phenylazo-2,4-dihydropyrazol-3-one and 3-amino-2-methylquinazolinone and with diamines; e.g., o-phenylenediamine, p-phenylenediamine, ethylenediamine, semicarbazide hydrochloride and thiosemicarbazide under different conditions. On the other hand, compound (2) reacted with both sodium azide and active methylene compounds, e.g., ethylcyanoacetate and ethylacetoacetate to give (19) and (20), respectively. All new prepared compounds were subjected to antimicrobial activity evaluation.

The Evaluation of Some Heterocycles as Antioxidant Additives for Lubricating Oils

Abstract 2-Phenyl-4-thienylidene-2-oxazolin-5-one I was prepared and reacted with 2-aminothiazole, p-aminophenol, and p-aminoacetophenone in the presence of acetic acid containing catalytic amounts of freshly fused sodium acetate to give the corresponding imidazolone derivatives II, III, and IV, respectively. A Claisen reaction of IV with ethylacetate gave the corresponding imidazolone V, which on reaction with phenylhydrazine in ethanol afforded the corresponding pyrazolinoimidazolone VI. On the other hand, I reacted with o- and p-phenylenediamines in ethanol and yielded the corresponding o- and p-aminophenylcarboxamide of α-phenyl carboxamido-β-thiophenoacrylic acids VII and VIII, respectively. The prepared products were evaluated as antioxidant additives for Egyptian lube oils. Some of these products showed good results.

Synthesis and evaluation of some new oxazolones and imidazolones as antioxidant additives for Egyptian lubricating oils

Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3–8, respectively. Moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9–14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16–19, respectively. Michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20–23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a–c, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. Measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.

The Synthesis and Evaluation of Some New Multifunction Additives for Egyptian Gasoline Motor Oils

Abstract 2-[2-(1,3-Diphenyl-1H-pyrazol-4-yl)-vinyl]-benzo[d][1,3]oxazin-4-one (2) was utilized as a key intermediate for the synthesis of some new quinazolinone derivatives incorporating diphenylpyrazole moiety. Treatment of benzoxazine derivative 2 with different amines, namely, p-phenylenediamine, p-anisidine, p-toluidine, sodiumazide, hydroxylamine hydrochloride, phenyl hydrazine, and hydrazine hydrate afforded pyrazolyl quinazoline derivatives 3, 4, 5, 6, 7, 9, and 10, respectively. Structure 10 was undergoing acetylation and benzoylation with acetic anhydride or benzoyl chloride to afford 11 and 12, respectively. Representative compounds of the synthesized products were established and evaluated as antioxidant and corrosion inhibitors for gasoline lube oils.

Synthesis of Some Novel Antioxidant and Anticorrosive Additives for Egyptian Lubricating Oils

Abstract The starting oxazolone 1 was reacted with p-aminophenol in glacial acetic acid to afford imidazolone 2, which afforded Mannich base 3 via the reaction with piperidine and paraformaldehyde. Moreover, the reaction of 2 with ethylchloroacetate or chloroacetic acid in dry acetone gave the corresponding imidazolones 4 and 5, respectively. Compound 4 reacted with benzylamine or 4-chlorobenzaldehyde to furnish 6 and 7, respectively. On the other hand, oxazolone 1 reacted with hydrazines in glacial acetic acid to afford the 1,2,4-triazines 11–15. Representative compounds of the synthesized products were established and evaluated as antioxidant and corrosion inhibitors for gasoline lube oils.

The Synthesis and Evaluation of Some New Quinazolones as Antioxidant Additives for Egyptian Lubricating Oils

4-(4-oxo-4H-benzo[d][1,3]oxazin-2-yl)phenyl-4-methylbenzenesulfonate 2 was prepared and reacted with some nitrogen and sulfur nucleophiles. The prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil in which compounds, 4-(3-amino-4-oxo-3,4-dihydroquinazolin-2-yl)phenyl-4-methylbenzene sulfonate 12, 4-(3-(3-chloro-2-oxo-4-phenylazetidin-1-yl)-4-oxo-3,4-dihydroquinazolin-2-yl)phenyl 4-methylbenzenesulfonate 14, 4-(4-oxo-3-(4-oxo-2-phenylthiazolidin-3-yl)-3,4-dihydroquinazolin-2-yl)phenyl 4-methylbenzenesulfonate 15, and 4-(3-(1,3-dioxoisoindolin-2-yl)-4-oxo-3,4-dihydroquinazolin-2-yl)phenyl 4-methylbenzenesulfonate 18 exhibited the highest antioxidant activity. It was interesting also to study the effect of concentration of additive 15 to find the optimum concentration recommended to be used, 0.1 g for 1 L oil of additive 15 was the more effective concentration to be used. Also, measurements of thermal analyses were carried out.

Synthesis and evaluation of some novel additives as antioxidants and corrosion inhibitors for petroleum fractions

Benzoxazinone 2 was prepared and reacted with formamide, acetamide, some primary aromatic amines and heterocyclic amines giving the corresponding quinazolone derivatives 3–15 respectively. The reaction of benzoxazinone 2 with hydrazine hydrate and phenyl hydrazine was also studied. Representative compounds of the synthesized products were evaluated as antioxidants and corrosion inhibitors for gasoline engine lubricating oil. The highest antioxidant activities were obtained with compounds 10–15. The optimum concentration recommended for these new additives was found to be 0.1g for 1L of oil for compounds 13–15. In addition, some of the highly effective antioxidant additives, namely 10–15, were thermally analyzed by using thermogravimetric analysis (TGA) and differential thermal gravimetric analysis (DTGA) techniques and the results indicated that compounds are thermally stable and could be used under thermal conditions. Moreover, a comparison of the oxidation stability between the tested oil containing the prepared products and lubricating oil containing commercial additives was also studied.