Synthesis of functionalized 2,3-dihydrothieno[2,3-d]pyrimidin-4(1H)-ones and their recyclization to 2,3-dihydrothieno[3,4-d]pyrimidin-4(1H)-ones

By the reaction of 6-aryl(alkyl)amino-5-cyano-2,3-dihydro-1,3-thiazin-4(10)-ones with α-halogenoketones in the presence of triethylamine, 2,3-dihydrothieno[2,3-d]pyrimidin-4(1H)-ones have been synthesized and their acid-catalyzed recyclization to 2,3-dihydrothieno[3,4-d]pyrimidin-4(1H)-ones has been found and studied. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:104–111, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20181     

Reaction of 6-oxo-, thioxo-2,3-dimethylthieno[2,3-d]pyrimidin-4-ones with electrophelic reagents

The reaction of 6-oxo-, thioxo-2,3-dimethylthieno[2,3-d]pyrimidin-4-ones with electrophilic agents was studied. It was shown that during nitration these compounds undergo electrophilic unco-substitution forming 3-nitro- and 2-nitro-6-oxo- and 2,3-dinitro-6-thioxothieno[2,3-d]pyrimidin-4-ones, respectively; the reaction of these compounds with bromine proceeds in other directions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1574–1576, November, 1993.     

Synthesis of 2-Trihalomethyl-3,4-dihydrothieno[2,3-d]pyrimidin-4-ones

At room temperature, N-(1-chloro-2,2,2-trihaloethylidene)-O-methyl urethanes react with 2-aminothiophenes to form N-(2-thienyl)-N'-(methoxycarbonyl)trihaloacetamidines, which when heated in boiling toluene undergo ring closure to form 2-trihalomethyl-3,4-dihydrothieno[2,3-d]pyrimidin-4-ones.     

QSAR Study on Some N-[5-（2-Furanyl）-2-methyl- 4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-Substituted-5-（2-furanyl）-2-methyl-3H-thieno- [2,3-d]pyrimidin-4-ones Using Three-dimensional Holographic Vector of Atomic Interaction Field

Study on the quantitative structure-activity relationship （QSAR） of 26 compounds, N-[5-（2-furanyl）-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-substituted- 5-（2-furanyl）-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones, with three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） was carried out. SMR-PLS QSAR models have been created and good correlation coefficients and cross-validated correlation coefficients were obtained. The result shows that the models have good prediction capability and favorable stability and the 3D-HoVAIF is applicable to the molecular structural characterization and biological activity prediction.     

A new route to 7-substituted derivatives of n-[4-(2-[2-amino-3,4-dihydro-4-oxo-7H-pyrrolo(2,3-d)pyrimidin-5-yl]ethyl)benzoyl]-L-glutamic acid [ALIMTA (LY231514, MTA)

Alkylation of various primary amines with crotyl bromide, followed by DMAP-promoted acylation with methyl malonyl chloride to 4 and then manganic triacetate dihydrate/cupric acetate induced radical cyclization, gave 1-substituted-4-vinyl-3-carbomethoxy-2-pyrrolidinones (5). Thiation to the thiolactams 6 and guanidine cyclization then gave a series of 2-amino-3,4-dihydro-4-oxo-5-vinyl-7-substituted pyrrolo[2,3-d]pyrimidines (7). Palladium-catalyzed C-C coupling with diethyl 4-iodobenzoylglutamate led in one step via an unexpected redox reaction to the diethyl esters 9 of a series of 7-substituted derivatives of ALIMTA (LY231514, MTA), from which the target analogues 10 were readily prepared by saponification. Attempted deprotection at position 7 was successful in only one case (9d, R = CH(2)C(6)H(3)(OMe)(2)(-3',4'), which resulted in a known pentultimate precursor (9, R = H) of ALIMTA. The 7-substituted derivatives 10 proved to be inactive in vitro as inhibitors of cell division.     

Synthesis and Crystal Structure of Ethyl 3-（4-Chlorophenyl）-3,4-dihydro-6-methyl-4-oxo-2- （pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate

The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215（9）, b = 8.5311（4）, c = 21.6886（9） A^°, β = 91.607（1）°, V = 3814.0（3）A^°^3, Z = 8, Dc = 1.400 g/cm^3, F（000） = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.     

Synthesis of derivatives of 2-oxo-2,3-dihydro-1H-thieno[3,4-d]imidazole

Conclusions Derivatives of 2-oxo-2,3-dihydro-1H-thieno[3,4-d]imidazole were synthesized from 4,5-di-substituted 2-imidazolinones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2381–2383, October, 1987.     

Synthesis of 1-[2-Methyl-6(8)-R-quinolin-4-yl]thiosemicarbazides

1-(2-Methylquinolin-4-yl)thiocemicarbazides and S-(2-methylquinolin-4-yl)thiosemicarbazide hydrochlorides were synthesized by reaction of 6(8)-substituted 4-chloro-2-methylquinolines with thiosemicarbazide under different conditions. Alkaline hydrolysis of the hydrochlorides afforded substituted 1-(2-methylquinolin-4-yl)thiosemicarbazides.     

Synthesis,Crystal Structure,and Antitumor Activity of 1-（4-Methoxybenzylidene）-2-（1-phenyl-6-trifluoromethyl- 1H-pyrazolo [3,4-d] pyrimidin-4-yl）hydrazine Monohydrate

The novel title compound 1-(4-methoxybenzylidene)-2-(1-phenyl-6-trifluoromethyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)hydrazine monohydrate(C20H15F3N6O·H2O, Mr = 430.40) has been synthesized by a four-step procedure including the cyclization, chlorination, hydrazinolysis and condensation reaction, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space group Pbca with a = 8.3779(13), b = 17.607(3), c = 26.774(4) , V = 3949.2(11) 3, Z = 8, Dc = 1.448 g/cm3, μ = 0.117 mm–1, F(000) = 1776, the final R = 0.0553 and wR = 0.1516 for 2354 observed reflections with I 2■(I). X-ray diffraction analysis reveals that the title compound is almost coplanar except for the trifluoromethyl and phenyl moieties. In the crystal packing, the molecules are linked by intermolecular O(1W)–H(1WA)···N(2), O(1W)–H(1WA)···N(4) and N(5)–H(5A)···O(1W) hydrogen bonds via water molecules and stacked through π-π stacking interactions. The preliminary bioassay suggested that the title compound exhibits relatively good antitumor activity against HepG2 and BCG-823.     

Synthesis of 2-amino-6,7-dihydrothieno-[3′,2′:5,6]pyrido[2,3-d]pyrimidin-4-one

2-Amino-6,7-dihydrothieno[3′,2′:5,6]pyrido[2,3-rf]pyrimidin-4-one ( 1 ) was prepared in three steps from S-(3-butynyl)thiosemicarbazide hydroiodide ( 3 ) and diethyl ketomalonate. The featured step in this synthetic sequence was an intramolecular Diels-Alder reaction of the in situ generated 3-(3-butynylthio)-6-carboethoxy-5-chloro-1,2,4-triazine ( 9 ) to provide the key intermediate 5-carboethoxy-6-chloro-2,3-dihydrothieno-[2,3-b]pyridine ( 6 ). In the course of studies directed toward the preparation of 1 , thermolysis of 3-(3-butynyl-thio)-6-carboethoxy-1,2,4-triazin-5(2H)-one ( 2 ) was found to involve competitive intramolecular Diels-Alder and intramolecular coplanar cycloamination processes, providing the 2,3-dihydrothieno[2,3-b]pyridin-6(7H)-one ( 4 ) and the 1,3-thiazino[3,2-b]-1,2,4-triazin-3-one (5) derivatives, respectively.     

Efficient Synthesis of 6-(1H-1,2,4-Triazol-1-yl)-thieno[2,3-d]pyrimidin-4(3H)-ones via an Iminophosphorane

Ethyl 2-amino-4-methyl-5-(1H-1,2,4-triazol-1-yl)thiophene-3-carboxylate 2, obtained from Gewald reaction of 1-(1H-1,2,4-triazol-1-yl)acetone 1 with ethyl cyanoacetate and sulfur, was transferred into iminophosphorane 3. Further reaction of 3 with aromatic isocyanates gave carbodiimides 4, which were treated subsequently with a secondary amine to give 6-(1H-1,2,4-triazol-1-yl)-thieno[2,3-d]pyrimidin-4(3H)-ones 6 in good yields in the presence of a catalytic amount of sodium ethoxide.     

Synthesis and Structure of 5-Aryl-4-[hydroxy(phenyl)methylene]-1-[2-(1H-indol-3-yl)ethyl]pyrrolidine-2,3-diones

Russian Journal of General Chemistry - The reactions of tryptamine with aromatic aldehyde and methyl benzoylpyruvate at room temperature leads to the formation of...     

A Facile One Pot Synthesis of 2-Aryl-4-[2H-2-oxo-[1]benzopyran-3-yl] 2,3-dihydro and 2,5-Dihydro-1,5-benzothiazepines

3-acetyl coumarins on condensation with various aromatic aldehydes in the presence of piperidine gave corresponding chalcones in a solid state under solvent free conditions. These chalcones are isolated and characterized. The in-situ-formed chalcones (1) are also converted into corresponding 2-aryl-4-[2H-2-oxo[1]benzopyran-3-yl]-2,3-dihydro (3) and 2,5-dihydro-1,5-benzothiazepines (4) in one step by interacting with orthoamino thiophenol. Both the 2,3-dihydro (3) and 2,5-dihydrobenzothiazepines (4) have been converted into same tetrahydrobenzothiazepine (5). Finally, the tetrahydrobenzo thiazepine (5) is converted into its acetyl derivative (11). The structures of the title compounds have been confirmed on the basis of their microanalytical, IR, ¹ H NMR, and mass spectral data.     

Synthèse des pyrido[2,3-d] el [3,2-d] -s-triazolo[3,4-f] pyrimidines el de (pyrazolyl-1')-4 pyrido[2,3-d] et [3,2-d] pyrimidines

The synthesis of two new heterocycles is described: pyrido-[2,3-d]-.s-triazolo[ 3,4-f] pyrimidine and pyrido[3,2-d]-.s-triayzolo-[3,4-f] pyrimidine. 4-[I'-Pyrazolyl]pyrido[2,3-d]pyrimidines and 4-[1′-pyrazoly1] pyrido[ 3,2-d] pyrimidine are obtained by the action of 4-hydrazinopyrido[2,3-d]pyrimidine and 4-hydrazinopyrido-[3,2-d]pyrimidine with several β-diketones.     

Synthesis and Crystal Structure of 1,2-Bis(1-phenyl-3-methylthio- 4-iminopyrazolo[3,4-d]pyrimidin-5-yl) ethane

1 INTRODUCTION As purine analogs, pyrzolo[3,4-d]pyrimidines have anti-tumor[1], antibacterial[2] and anti-leukemic activities[3,4]. Few of these, however, have been studied for pesticidal activity. It is reported that some substituted pyrzolo[3,4-d]pyrimidines have good fungicidal activity[5~7]. These prompted us to study pyrazolo[3,4-d]pyrimidines analogs further. It is shown that two possible products can be formed in the reaction of ethyl N-pyrazolylformimidate with alkylamines as sh…