Chemoselective Alkylation of 3- and 4-(5-Amino-4-hetaryl-2,3-dihydro-3-oxopyrrol-1-yl)benzoic Acids

Alkylation of 3- and 4-(5-amino-4-hetaryl-2,3-dihydro-3-oxopyrrol-1-yl)benzoic acids with phenacyl bromides or chloroacetanilides in DMF in the presence of triethylamine occurs at the carboxy group with high selectivity and yields the corresponding phenacyl and arylcarbamoylmethyl esters. The initial pyrrolylbenzoic acids were synthesized by reaction of 3- and 4-aminobenzoic acids with 4-chloro-2-hetaryl-3-oxo-butyronitriles.     

Synthesis of 5-Amino-1-aryl-4-(4-aryl-1,3-thiazol-2-yl)- 2,3-dihydro-1H-pyrrol-3-ones*

Reactions of 2-(4-aryl-1,3-thiazol-2-yl)-3-oxo-4-chlorobutyronitriles with primary aromatic amines result in nucleophilic substitution of the chlorine atom by amino group, followed by intramolecular addition of the secondary amino group to the cyano group. The products are 5-amino-1-aryl-4-(4-aryl-1,3-thiazol-2-yl)- 2,3-dihydro-1H-pyrrol-3-ones which are structurally related to the known antiischemic drugs.     

Synthesis of 3-(3-Acetyl-5-aryl-2,3-dihydro-1,3,4-oxadiazol-2-yl)chromones

A method is proposed for the synthesis of 3-(3-acetyl-5-aryl-2,3-dihydro-1,3,4-oxadiazol-2-yl)chromones which consists of the conversion of 3-formylchromones to aroylhydrazones and their subsequent heterocyclization using acetic anhydride.     

Synthesis of 3-[5-anilino-(2,3-d)-dioxole-1,3]-1-oxo-1,3-dihydro-2-benzofurane

A microscale synthesis (500 mg) of the product 3-[5-anilino-(2,3-d)-dioxole-1,3]-1-oxo-1, 3-dihydro-2-benzofurane (COR.01.126) is described. This method, which requires only four steps, is principally available for the ¹⁴C-labeled synthesis with labeled phthalic anhydride as starting material.     

Synthesis of 3- and 5-amino-5-(3)-(pyrrol-2-yl)isoxazoles

5-Amino-3-(pyrrol-2-yl)isoxazoles were selectively prepared by the reaction of 2-(2,2-dicyano-1-ethylthioethenyl)pyrroles with hydroxylamine in methanol. Under analogous conditions, 2-(2-carbamoyl-2-cyano-1-ethylthioethenyl) pyrroles with hydroxylamine gave 5-aminoisoxazoles and their structural isomers, 3-aminoisoxazoles (3-5% yield). The latter were selectively prepared by reacting 2-(2-carbamoyl-2-cyano-1-ethylthioethenyl)pyrroles with hydroxylamine in the presence of aqueous NaOH and from the products of intramolecular cyclization of 2-(2-carbamoyl-2-cyano-1-ethylthioethenyl)pyrroles, 1-ethylthio-3-iminopyrrolizines and hydroxylamine.     

Thermal oligomerization of methyl 4-(1,3-dioxo-2,3-dihydro-1H-isoindol-2-yl)buta-2,3-dienoate

Dimeric compounds formed as a result of thermal oligomerization of methyl 4-(1,3-dioxo-2,3- dihydro-1H-isoindol-2-yl)buta-2,3-dienoate were identified.     

Synthesis of 5-amino-4-hetaryl-2,3-dihydro-1h-3-pyrrolones

2-Hetaryl-3-oxo-4-phthalimidobutyronitriles (and pentanonitriles) were obtained with high yields by C-acylation of hetarylacetonitriles with N-phthaloylglycine and -alanine chlorides respectively under the conditions of base catalysis. Hydrazinolysis of the phthaloyl protection in these compounds leads to the formation of 5-amino-4-hetaryl-2,3-dihydro-1H-3-pyrrolones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1783–1790, December, 2004.     

Synthesis and Transformations of Ethyl (Z)-2-(2,3-dihydro-1,3-dioxo-1H-isoindol-2-yl)-3-(dimethylamino)propenoate

Ethyl (Z)-2-(2,3-dihydro-1,3-dioxo-1H-isoindol-2-yl)-3-(dimethylamino)propenoate was prepared in one step from ethyl (2,3-dihydro-1,3-dioxo-1H-isoindol-2-yl)acetate and bis(dimethylamino)-tert-butoxymethane and treated with various amines and hydrazines to afford the corresponding amino substituted products. Reactions of the titled compound with N,N'-, C,N-, and C,O'-ambident nucleophiles in refluxing acetic acid furnished the corresponding fused pyrimidinones, quinolizinones, and pyranones.     

3-（3-乙酰基-5-芳氧亚甲基-2,3-二氢-1,3,4-噁二唑-2-基）色酮类化合物的合成

3-（3-乙酰基-5-芳氧亚甲基-2;3-二氢-1;3;4-噁二唑-2-基）色酮类化合物的合成;噁二唑啉;色酮;合成     

Synthesis of New {2-[3(4)-Nitrophenyl]-5-chloromethyl-1,3-dioxan-5-yl}methyl-4-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl) Benzoates

Russian Journal of General Chemistry - The reaction of 2-[3(4)-nitrophenyl]-5,5-dichloromethyl-1,3-dioxanes with potassium 4-aminobenzoate in dimethylformamide gave...     

Synthesis of 2-[5-amino-2,3-dihydro-4H-imidazol-4-ylidene]malononitriles

Using the system of tetracyanoethylene, ammonium acetate and a carbonyl compound, the preparation of 2-[5-amino-2,3-dihydro-4H-imidazol-4-ylidene]malononitriles was carried out. The structures of these new dihydroimidazoles were determined by NMR experiments and by X-ray crystallography.     

Synthesis of 7-iodo(arylsulfanyl)methyl-7,8-dihydro-[1,3]thiazolo[2,3-i]purinium pentaiodide (perchlorates) and their transformation into 4-amino-5-(1,3-thiazol-2-yl)imidazole derivatives

Intramolecular electrophilic cyclization of 6-allylsulfanylpurine by the action of iodine and arenesulfenyl chlorides gave 7-iodomethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium pentaiodide and 7-arylsulfanylmethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium perchlorates, respectively. 7-Iodomethyl-7,8-dihydro-[1,3]thiazolo[2,3-i]purin-6-ium iodide reacted with sodium and potassium alkoxides to produce alkyl N-[5-(4-methyl-1,3-thiazol-2-yl)-1H-imidazol-4-yl]formimidates, and its reaction with secondary cyclic amines afforded 5-(4-methyl-1,3-thiazol-2-yl)-N-[morpholin-4-yl(or piperidin-1-yl)methylidene]-1H-imidazol-4-amines. Successive treatment of 7-arylsulfanylmethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium perchlorates with sodium acetate and morpholine led to the formation of 5-(4-arylsulfanylmethyl-4,5-dihydro-1,3-thiazol-2-yl)-N-(morpholin-4-ylmethylidene)-1H-imidazol-4-amines.     

Synthesis of 5-amino-1,3-dimethylpyrazol-4-yl aryl ketones

A convenient preparation of 5-amino-1,3-dialkylpyrazol-4-yl heterocyclic ketones is reported. They are prepared from the reaction of heterocyclic esters with the di-lithio derivative from N-(4-bromo-1,3-dimethyl-1H-pyrazol-5-yl)benzamide ( 1 ).