2-Chloro-3-methylquinoxaline reacts with aromatic amines in basic medium forming 2-arylamino-3-methylquinoxalines, also it reacts with mercaptoacetic acid. The 3-methyl-2(1H)-quinoxalinone condenses with aromatic aldehydes forming the corresponding 3-(substituted styryl)-2(1H)-quinoxalinones which add bromine in acetic acid to yield the corresponding dibromo derivatives which react with morpholine, sodium methoxide, and piperidine to give the corresponding compounds. 3-Methyl-2(1H)-quinoxalinone undergoes side-chain bromination to yield 3-bromomethyl-2(1H)-quinoxalinone, which reacts with aromatic amines, sodium salt of saccharine, potassium phthalimide··· 3-Methyl-2(1H)-quinoxalinone with P2S5 gave 3-methyl-2(1H)-quinoxalinethione which reacts with 2-aminoethanol, dimethyl sulfate, and halo acids

2-Chloro-3-methylquinoxaline reacts with aromatic amines in basic medium forming 2-arylamino-3-methylquinoxalines, also it reacts with mercaptoacetic acid. The 3-methyl-2(1H)-quinoxalinone condenses with aromatic aldehydes forming the corresponding 3-(substituted styryl)-2(1H)-quinoxalinones which add bromine in acetic acid to yield the corresponding dibromo derivatives which react with morpholine, sodium methoxide, and piperidine to give the corresponding compounds. 3-Methyl-2(1H)-quinoxalinone undergoes side-chain bromination to yield 3-bromomethyl-2(1H)-quinoxalinone, which reacts with aromatic amines, sodium salt of saccharine, potassium phthalimide··· 3-Methyl-2(1H)-quinoxalinone with P2S5 gave 3-methyl-2(1H)-quinoxalinethione which reacts with 2-aminoethanol, dimethyl sulfate, and halo acids

2-Chloro-3-methylquinoxaline reacts with aromatic amines in basic medium forming 2-arylamino-3-methylquinoxalines, also it reacts with mercaptoacetic acid. The 3-methyl-2(1H)-quinoxalinone condenses with aromatic aldehydes forming the corresponding 3-(substituted styryl)-2(1H)-quinoxalinones which add bromine in acetic acid to yield the corresponding dibromo derivatives which react with morpholine, sodium methoxide, and piperidine to give the corresponding compounds. 3-Methyl-2(1H)-quinoxalinone undergoes side-chain bromination to yield 3-bromomethyl-2(1H)-quinoxalinone, which reacts with aromatic amines, sodium salt of saccharine, potassium phthalimide··· 3-Methyl-2(1H)-quinoxalinone with P2S5 gave 3-methyl-2(1H)-quinoxalinethione which reacts with 2-aminoethanol, dimethyl sulfate, and halo acids

Reaction of 3-methyl-2(1H)quinoxalinone (1) with alkyl, benzyl, and arenesulfonyl halides in the presence of K2CO3 in dry acetone gave 1-substituted 3-methyl-2(1H)-quinoxalinones (2a–g). However 1 reacts with benzoyl chloride under the same conditions to give 3-methyl-2-quinoxalinyl benzoate, while it reacts with P2S5 in dry pyridine to give 3-methyl-2(1H)quinoxalinethione (4). Treatment of 4 with methy iodide in the presence of K2CO3 in dry acetone gave 2-methyl-3-(methylthio)quinoxaline but not 1,3-dimethyl-2(1H)-quinoxalinethione which has been obtained from 2a and P2S5 in dry pyridine. Treatment of 4 with benzyl bromide and/or p-nitrobenzyl bromide in the presence of K2CO3 in dry acetone gave 2-benzylthio and 2-(p-nitrobenzylthio)-3-methylquinoxalines. Syntheses of 1-methyl-3-(substituted styryl)-2(1H)-quinoxalinone (8a–m) were achieved by condensation of 2a with aromatic aldehydes. Addition of thiophenols and mercaptoacetic acid to 8 gives 1-methyl-3-[2-(substituted phenylthio)ethyl]-2(1H)-quinoxalinones and 1-methyl-3-[2-(substituted phenyl)-2-(carboxymethylthio)ethyl]-2(1H)-quinoxalinones respectively. 1,3-Dimethyl-2(1H)-quinoxalinone (2a) condensed with ketones in the presence of ZnCl2 to give 1-methyl-3-[2-(substituted phenyl)-1-alkenyl]-2(1H)-quinoxalinones. 1-Methyl-3-(substituted styryl)-2(1H)-quinoxalinethiones were produced by refluxing a mixture of 8 with P2S5 in dry pyridine

Reaction of 3-methyl-2(1H)quinoxalinone (1) with alkyl, benzyl, and arenesulfonyl halides in the presence of K2CO3 in dry acetone gave 1-substituted 3-methyl-2(1H)-quinoxalinones (2a–g). However 1 reacts with benzoyl chloride under the same conditions to give 3-methyl-2-quinoxalinyl benzoate, while it reacts with P2S5 in dry pyridine to give 3-methyl-2(1H)quinoxalinethione (4). Treatment of 4 with methy iodide in the presence of K2CO3 in dry acetone gave 2-methyl-3-(methylthio)quinoxaline but not 1,3-dimethyl-2(1H)-quinoxalinethione which has been obtained from 2a and P2S5 in dry pyridine. Treatment of 4 with benzyl bromide and/or p-nitrobenzyl bromide in the presence of K2CO3 in dry acetone gave 2-benzylthio and 2-(p-nitrobenzylthio)-3-methylquinoxalines. Syntheses of 1-methyl-3-(substituted styryl)-2(1H)-quinoxalinone (8a–m) were achieved by condensation of 2a with aromatic aldehydes. Addition of thiophenols and mercaptoacetic acid to 8 gives 1-methyl-3-[2-(substituted phenylthio)ethyl]-2(1H)-quinoxalinones and 1-methyl-3-[2-(substituted phenyl)-2-(carboxymethylthio)ethyl]-2(1H)-quinoxalinones respectively. 1,3-Dimethyl-2(1H)-quinoxalinone (2a) condensed with ketones in the presence of ZnCl2 to give 1-methyl-3-[2-(substituted phenyl)-1-alkenyl]-2(1H)-quinoxalinones. 1-Methyl-3-(substituted styryl)-2(1H)-quinoxalinethiones were produced by refluxing a mixture of 8 with P2S5 in dry pyridine

Reaction of 3-methyl-2(1H)quinoxalinone (1) with alkyl, benzyl, and arenesulfonyl halides in the presence of K2CO3 in dry acetone gave 1-substituted 3-methyl-2(1H)-quinoxalinones (2a–g). However 1 reacts with benzoyl chloride under the same conditions to give 3-methyl-2-quinoxalinyl benzoate, while it reacts with P2S5 in dry pyridine to give 3-methyl-2(1H)quinoxalinethione (4). Treatment of 4 with methy iodide in the presence of K2CO3 in dry acetone gave 2-methyl-3-(methylthio)quinoxaline but not 1,3-dimethyl-2(1H)-quinoxalinethione which has been obtained from 2a and P2S5 in dry pyridine. Treatment of 4 with benzyl bromide and/or p-nitrobenzyl bromide in the presence of K2CO3 in dry acetone gave 2-benzylthio and 2-(p-nitrobenzylthio)-3-methylquinoxalines. Syntheses of 1-methyl-3-(substituted styryl)-2(1H)-quinoxalinone (8a–m) were achieved by condensation of 2a with aromatic aldehydes. Addition of thiophenols and mercaptoacetic acid to 8 gives 1-methyl-3-[2-(substituted phenylthio)ethyl]-2(1H)-quinoxalinones and 1-methyl-3-[2-(substituted phenyl)-2-(carboxymethylthio)ethyl]-2(1H)-quinoxalinones respectively. 1,3-Dimethyl-2(1H)-quinoxalinone (2a) condensed with ketones in the presence of ZnCl2 to give 1-methyl-3-[2-(substituted phenyl)-1-alkenyl]-2(1H)-quinoxalinones. 1-Methyl-3-(substituted styryl)-2(1H)-quinoxalinethiones were produced by refluxing a mixture of 8 with P2S5 in dry pyridine

1-(Phenylthio)- and 1-(hydroxycarbonylmethylthio)-4-methylphthalazines were prepared from 1-chloro-4-methylphthalazines (1). A series of 2-benzyl- and benzenesulphonyl derivatives was prepared from the corresponding halides and 4-methyl-1(2H)-phthalazinone (4). 4-Methyl-1(2H)-phthalazinthione (6) was substituted at SH group to give 1-(benzylthio)- and 1-(ethoxycarbonylmethylthio)-4-methylphthalazines, 7 and 8 respectively. Treatment of hydrazine hydrate with 8 produced 1-hydrazino-4-methylphthalazine (10). However, when the latter compound was treated with 1 it gave 1,2-bis-(4-methylphthalazinyl)hydrazine. Treatment of 10 with aromatic aldehydes in glacial acetic acid gave the corresponding 3-phenyl-s-triazolo-[3,4-a]-6-methylphthalazines 13. 1-Hydrazino-4-methylphthalazine (10) underwent cyclization reactions with acetic anhydride, ethyl chloroformate, carbon disulphide, ethylformate, ethyl oxalate and with nitrous acid to give the corresponding triazolo-, triazino- and tetrazolophthalazine compounds

1-(Phenylthio)- and 1-(hydroxycarbonylmethylthio)-4-methylphthalazines were prepared from 1-chloro-4-methylphthalazines (1). A series of 2-benzyl- and benzenesulphonyl derivatives was prepared from the corresponding halides and 4-methyl-1(2H)-phthalazinone (4). 4-Methyl-1(2H)-phthalazinthione (6) was substituted at SH group to give 1-(benzylthio)- and 1-(ethoxycarbonylmethylthio)-4-methylphthalazines, 7 and 8 respectively. Treatment of hydrazine hydrate with 8 produced 1-hydrazino-4-methylphthalazine (10). However, when the latter compound was treated with 1 it gave 1,2-bis-(4-methylphthalazinyl)hydrazine. Treatment of 10 with aromatic aldehydes in glacial acetic acid gave the corresponding 3-phenyl-s-triazolo-[3,4-a]-6-methylphthalazines 13. 1-Hydrazino-4-methylphthalazine (10) underwent cyclization reactions with acetic anhydride, ethyl chloroformate, carbon disulphide, ethylformate, ethyl oxalate and with nitrous acid to give the corresponding triazolo-, triazino- and tetrazolophthalazine compounds

1-(Phenylthio)- and 1-(hydroxycarbonylmethylthio)-4-methylphthalazines were prepared from 1-chloro-4-methylphthalazines (1). A series of 2-benzyl- and benzenesulphonyl derivatives was prepared from the corresponding halides and 4-methyl-1(2H)-phthalazinone (4). 4-Methyl-1(2H)-phthalazinthione (6) was substituted at SH group to give 1-(benzylthio)- and 1-(ethoxycarbonylmethylthio)-4-methylphthalazines, 7 and 8 respectively. Treatment of hydrazine hydrate with 8 produced 1-hydrazino-4-methylphthalazine (10). However, when the latter compound was treated with 1 it gave 1,2-bis-(4-methylphthalazinyl)hydrazine. Treatment of 10 with aromatic aldehydes in glacial acetic acid gave the corresponding 3-phenyl-s-triazolo-[3,4-a]-6-methylphthalazines 13. 1-Hydrazino-4-methylphthalazine (10) underwent cyclization reactions with acetic anhydride, ethyl chloroformate, carbon disulphide, ethylformate, ethyl oxalate and with nitrous acid to give the corresponding triazolo-, triazino- and tetrazolophthalazine compounds