1 -ethoxycarbonyl-2-

An unusual reaction was reported in which 2-(4-pyridyl)-4-carboxyethylthiazole (50) prepared from thioisonicotinamide (49) and ethylbromopyruvate (48) was converted to 51, which upon treatment with KNCS in the presence of NaHCOj gave 52 (618). This was again cyclized with 48 to yield 2-(4-pyridyI)-4-(4-ethoxycarbonyl-2-thiazolyl hydrazino-carbonyl)thiazole (S3) (Scheme 24). 

Reaction of various pyridazine derivatives with nitromethane or nitroethane in DMSO affords the corresponding 5-methyl and 5-ethyl derivatives. The reaction proceeds as a nucleophilic attack of the nitroalkane at the position 5. In this way, 3,6-dichloro-4-cyano-pyridazine, 4-carboxy- and 4-ethoxycarbonyl-pyridazin-3(2//)-ones and 4-carboxy- and 4-ethoxycarbonyl-pyridazin-6(lH)-ones can be alkylated at position 5 (77CPB1856). 

Oxepin, 4-ethoxycarbonyl-2,3,6,7-tetrahydro-synthesis, 7, 578 Oxepin, 2-methyl-enthalpy of isomerization, 7, 555 Oxepin, 2,3,4,5-tetrahydro-reduction, 7, 563 synthesis, 7, 578 Oxepin, 2,3,4,7-tetrahydro-synthesis, 7, 578 Oxepin, 2,3,6,7-tetrahydro-oxidation, 7, 563 reduction, 7, 563 Oxepin-2,6-dicarboxylic acid stability, 7, 565 Oxepinium ions synthesis, 7, 559 Oxepins, 7, 547-592 antiaromaticity, 4, 535 applications, 7, 590-591 aromatization, 7, 566 bond lengths and angles, 7, 550, 551 cycloaddition reactions, 7, 27, 569 deoxygenation, 7, 570 dipole moment, 7, 553 disubstituted synthesis, 7, 584... 

Pteridine, 2,4-disubstituted-6-halo-synthesis, 3, 292 Pteridine, 2-ethoxycarbonyl-structure, 3, 276 Pteridine, 4-ethoxycarbonyl-structure, 3, 276... 

Thiazole, 5-amino-4-ethoxycarbonyl-2-methyl-synthesis, 6, 306 Thiazole, 2-amino-4-(2 -furyl)-bromination, 6, 256 Thiazole, 2-amino-4-hydroxy-synthesis, 6, 296 Thiazole, 5-amino-2-hydroxy-synthesis, 6, 301 Thiazole, 5-amino-2-mercapto-synthesis, 6, 301 Thiazole, 2-amino-4-methyl-alkylation, 6, 256 synthesis, 6, 300 Thiazole, 2-amino-5-nitro-antiparasitic activity, 1, 180... 

Methadone hydrochloride (2-dimethylamino-4-ethoxycarbonyl-4,4-diphenylbutane HCl) [W95-90-5J M 345.9, m 241-242 , pKj 8.94, pK 10.12 (free base). Crystd from EtOH. 

A -Acylated 3-hydroxypyrroles prefer the oxo form (87TL4395 90LA 397). Compounds of type 116 [5-(2-acylhydrazino)-4-ethoxycarbonyl)-2-oxo-2//-pyrrole-3-acetate] are in a tautomeric equilibrium with the corresponding acylhydrazones 117 (95H1479). 

Treatment of alkyl 9-benzyloxycarbonyl-3-methyl-6-oxo-2/7,6//-pyr-ido[2,l-f ][l,3]thiazine-4-carboxylates with BBr3 in CH2CI2 at -70 °C for 0.5-1 h and at room temperature for 3h yielded 9-carboxyl derivatives. The decarboxylation of these acids was unsuccessful. Hydrolysis of diethyl cA-3,4-H-3,4-dihydro-3-methyl-6-oxo-2//,6//-pyrido[2,l-f ][l,3]thiazine-4,9-dicarboxylate in aqueous EtOH with KOH at room temperature for 3 days yielded 4-ethoxycarbonyl-3,4-dihydro-3-methyl-6-oxo-2//,6//-pyrido-[2,l-f ] [1,3]thiazine-9-carboxylic acid (00JCS(P1)4373). Alkyl 9-hydroxy-methyl-3-methyl-6-oxo-3,4-dihydro-2//,6//-pyrido[2,l-f ][l,3]thiazine-4-car-boxylates were O-acylated with AC2O and (PhC0)20 in pyridine at room temperature for 12-48h. 

Treatment of 8-[(4-cyanophenyl)methoxy]-7-formyl-2-cyclopentyl-2,3,4,6,11,1 la-hexahydro-l//-pyrazino[l,2-i]isoquinoline-l,4-dione with (Et0)2P(0)CH2C00Et and NaH in THF at 40 °C overnight, or with (2-pyridylmethyl)-, 4-[(ethoxycarbonyl)benzyl]-, (4-nitrobenzyl)-, and (meth-oxymethyl)triphenylphosphonium halogenide in the presence of KH in THF at room temperature gave 7-ethylene derivatives 386 (98MIP7). 

Chemical Name 18-[ [4-[(Ethoxycarbonyl)oxy]-3,5-dimethoxybenzoyl] oxy] -11,17-di-methoxyyohimban-16-carboxylic acid methyl ester... 

The reaction of differently substituted 5-arylidenehydrazono-4-ethoxycarbonyl-3-methyl-(l/7)pyrazoles 194 (X = 2-NC>2, 4-NC>2, 2-Cl, 4-Me, 4-NMe2, 2-OMe) with bromine in acetic acid in the presence of sodium acetate leads mainly to 3-aryl-7-ethoxycarbonyl-6-methyl-(li/)pyrazolo[5,l-c][l,2,4]triazoles 195 (Scheme 7) <1977J(P1)2047>. 

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