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1.
Jessica Orrego Hernandez Jaime Portilla Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(5):363-368
Cyclohexylamine reacts with 5‐chloro‐3‐methyl‐1‐(pyridin‐2‐yl)‐1H‐pyrazole‐4‐carbaldehyde to give 5‐cyclohexylamino‐3‐methyl‐1‐(pyridin‐2‐yl)‐1H‐pyrazole‐4‐carbaldehyde, C16H20N4O, (I), formed by nucleophilic substitution, but with 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde the product is (Z)‐4‐[(cyclohexylamino)methylidene]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐one, C17H21N3O, (II), formed by condensation followed by hydrolysis. Compound (II) crystallizes with Z′ = 2, and in one of the two independent molecular types the cyclohexylamine unit is disordered over two sets of atomic sites having occupancies of 0.65 (3) and 0.35 (3). The vinylogous amide portion in each compound shows evidence of electronic polarization, such that in each the O atom carries a partial negative charge and the N atom of the cyclohexylamine portion carries a partial positive charge. The molecules of (I) contain an intramolecular N—H...N hydrogen bond, and they are linked by C—H...O hydrogen bonds to form sheets. Each of the two independent molecules of (II) contains an intramolecular N—H...O hydrogen bond and each molecular type forms a centrosymmetric dimer containing one R22(4) ring and two inversion‐related S(6) rings. 相似文献
2.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(10):784-790
The reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde and N‐benzylmethylamine under microwave irradiation gives 5‐[benzyl(methyl)amino]‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C19H19N3O, (I). Subsequent reactions under basic conditions, between (I) and a range of acetophenones, yield the corresponding chalcones. These undergo cyclocondensation reactions with hydrazine to produce reduced bipyrazoles which can be N‐formylated with formic acid or N‐acetylated with acetic anhydride. The structures of (I) and of representative examples from this reaction sequence are reported, namely the chalcone (E )‐3‐{5‐[benzyl(methyl)amino]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl}‐1‐(4‐bromophenyl)prop‐2‐en‐1‐one, C27H24BrN3O, (II), the N‐formyl derivative (3RS )‐5′‐[benzyl(methyl)amino]‐3′‐methyl‐1′,5‐diphenyl‐3,4‐dihydro‐1′H ,2H‐[3,4′‐bipyrazole]‐2‐carbaldehyde, C28H27N5O, (III), and the N‐acetyl derivative (3RS )‐2‐acetyl‐5′‐[benzyl(methyl)amino]‐5‐(4‐methoxyphenyl)‐3′‐methyl‐1′‐phenyl‐3,4‐dihydro‐1′H ,2H‐[3,4′‐bipyrazole], which crystallizes as the ethanol 0.945‐solvate, C30H31N5O2·0.945C2H6O, (IV). There is significant delocalization of charge from the benzyl(methyl)amino substituent onto the carbonyl group in (I), but not in (II). In each of (III) and (IV), the reduced pyrazole ring is modestly puckered into an envelope conformation. The molecules of (I) are linked by a combination of C—H…N and C—H…π(arene) hydrogen bonds to form a simple chain of rings; those of (III) are linked by a combination of C—H…O and C—H…N hydrogen bonds to form sheets of R 22(8) and R 66(42) rings, and those of (IV) are linked by a combination of O—H…N and C—H…O hydrogen bonds to form a ribbon of edge‐fused R 24(16) and R 44(24) rings. 相似文献
3.
James L. Wardell Janet M. S. Skakle John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(8):o462-o467
The molecules of methyl 3‐(2‐nitrophenylhydrazono)butanoate, C11H13N3O4, (I), and methyl 3‐(2,4‐dinitrophenylhydrazono)butanoate, C11H12N4O6, (II), both prepared from methyl 3‐oxobutanoate and the corresponding nitrophenylhydrazine, exhibit polarized molecular electronic structures; in each of (I) and (II), the molecules are linked into chains by a single C—H...O hydrogen bond. The molecules of 5‐hydroxy‐3‐methyl‐1‐phenyl‐1H‐pyrazole, C10H10N2O, (III), prepared by the reaction of methyl 3‐oxobutanoate and phenylhydrazine, are linked into chains by a single O—H...N hydrogen bond. The reaction between methyl 3‐oxobutanoate and 3‐nitrophenylhydrazine yields 5‐hydroxy‐3‐methyl‐1‐(3‐nitrophenyl)‐1H‐pyrazole, (IV), which when crystallized from acetone yields 4‐isopropylidene‐3‐methyl‐1‐(3‐nitrophenyl)‐1H‐pyrazol‐5(4H)‐one, C13H13N3O3, (V). 相似文献
4.
Caroline Charlier Bernadette Norberg Laurence Goossens Jean‐Pierre Hnichart Franois Durant 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o648-o652
Three related compounds containing a pyrazole moiety with vicinal phenyl rings featuring a methylsulfonyl substituent are described, namely 3‐methyl‐1‐[4‐(methylsulfonyl)phenyl]‐5‐phenyl‐1H‐pyrazole, C17H16N2O2S, ethyl 1‐[4‐(methylsulfonyl)phenyl]‐5‐phenyl‐1H‐pyrazole‐3‐carboxylate, C19H18N2O4S, and 1‐[4‐(methylsulfonyl)phenyl]‐3‐[3‐(morpholino)phenoxymethyl]‐5‐phenyl‐1H‐pyrazole, C27H27N3O4S. The design of these compounds was based on celecoxib, a selective cyclooxygenase‐2 (COX‐2) inhibitor, in order to study the influence of various substituents on COX‐2 and 5‐lipoxygenase (5‐LOX) inhibition. 相似文献
5.
Haruvegowda Kiran Kumar Hemmige S. Yathirajan Nagaraj Manju Balakrishna Kalluraya Ravindranath S. Rathore Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):768-776
The reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde with phenols under basic conditions yields the corresponding 5‐aryloxy derivatives; the subsequent reaction of these carbaldehydes with substituted acetophenones yields the corresponding chalcones, which in turn undergo cyclocondensation reactions with hydrazine in the presence of acetic acid to form N‐acetylated reduced bipyrazoles. Structures are reported for three 5‐aryloxycarbaldehydes and the 5‐piperidino analogue, and for two reduced bipyrazole products. 5‐(2‐Chlorophenoxy)‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C17H13ClN2O2, (II), which crystallizes with Z′ = 2 in the space group P, exhibits orientational disorder of the carbaldehyde group in each of the two independent molecules. Each of 3‐methyl‐5‐(4‐nitrophenoxy)‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C17H13N3O4, (IV), 3‐methyl‐5‐(naphthalen‐2‐yloxy)‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C21H16N2O2, (V), and 3‐methyl‐1‐phenyl‐5‐(piperidin‐1‐yl)‐1H‐pyrazole‐4‐carbaldehyde, C16H19N3O, (VI), (3RS)‐2‐acetyl‐5‐(4‐azidophenyl)‐5′‐(2‐chlorophenoxy)‐3′‐methyl‐1′‐phenyl‐3,4‐dihydro‐1′H,2H‐[3,4′‐bipyrazole] C27H22ClN7O2, (IX) and (3RS)‐2‐acetyl‐5‐(4‐azidophenyl)‐3′‐methyl‐5′‐(naphthalen‐2‐yloxy)‐1′‐phenyl‐3,4‐dihydro‐1′H,2H‐[3,4′‐bipyrazole] C31H25N7O2, (X), has Z′ = 1, and each is fully ordered. The new compounds have all been fully characterized by analysis, namely IR spectroscopy, 1H and 13C NMR spectroscopy, and mass spectrometry. In each of (II), (V) and (IX), the molecules are linked into ribbons, generated respectively by combinations of C—H…N, C—H…π and C—Cl…π interactions in (II), C—H…O and C—H…π hydrogen bonds in (V), and C—H…N and C—H…O hydrogen bonds in (IX). The molecules of compounds (IV) and (IX) are both linked into sheets, by multiple C—H…O and C—H…π hydrogen bonds in (IV), and by two C—H…π hydrogen bonds in (IX). A single C—H…N hydrogen bond links the molecules of (X) into centrosymmetric dimers. Comparisons are made with the structures of some related compounds. 相似文献
6.
James W. Pavlik Heather S T. Martin Karen A. Lambert Jennifer A. Lowell Vikki M. Tsefrikas Cheryl K. Eddins Naod Kebede 《Journal of heterocyclic chemistry》2005,42(2):273-281
5‐Phenylisoxazole ( 4 ) and 4‐phenylisoxazole ( 22 ) underwent phototransposition to 5‐phenyloxazole ( 5 ) and 4‐phenyloxazole ( 24 ) respectively. Labeling with deuterium or methyl confirmed that these phototranspositions occurred via the P4 pathway which involves only interchange of the N2 and C3 ring position. Thus, 4‐deuterio‐5‐phenylisoxazole ( 4‐4d ), 4‐methyl‐5‐phenylisoxazole ( 10 ), and 5‐methyl‐4‐phenylisoxazole ( 23 ) phototransposed to 4‐deuterio‐5‐phenyloxazole ( 5‐4d ), 4‐methyl‐5‐phenyloxazole ( 11 ), and 5‐methyl‐4‐phenyloxazole ( 25 ) respectively. In addition to phototransposition, isoxazoles 4, 10 , and 23 also underwent photo‐ring cleavage to yield benzoylacetonitrile (9), α‐benzoylpropionitrile ( 15 ), and aceto‐α‐phenylacetonitrile ( 26 ) respectively. Irradiation of 5‐phenyl‐3‐(trifluoromethyl)isoxazole ( 16 ) in acetonitrile led to 5‐phenyl‐2‐(trifluoromethyl)oxazole ( 17 ), the P4 phototransposition product. Irradiation of 16 in methanol led to a substantial decrease in the yield of 17 and to the formation of a mixture of (E) and (Z)‐2‐methoxy‐2‐(trifluoromethyl)‐3‐benzoylaziridines 18a and 18b . 相似文献
7.
Aleksei B. Sheremetev Igor L. Yudin Nadezhda V. Palysaeva Kyrill Yu. Suponitsky 《Journal of heterocyclic chemistry》2012,49(2):394-401
The annulation reaction of vinamidinium salt containing nitrofurazanyl moiety at the β‐position gives access to the corresponding pyrazole. At nitration, two nitro groups were installed to the pyrazole ring. The synthesized 3‐(3,5‐dinitropyrazol‐4‐yl)‐4‐nitrofurazan 13 is strong NH acid and a new family energetic salts was prepared by direct neutralization with high nitrogen bases. Compound 13 crystallizes in the monoclinic space group P21/c, and charaterized by high density of 1.979 g/cm3 (at 100 K). J. Heterocyclic Chem., (2012). 相似文献
8.
Nabila Aït‐Baziz Yahia Rachedi Maamer Hamdi Artur M. S. Silva F. Balegroune Roisnel Thierry N. Sellier 《Journal of heterocyclic chemistry》2004,41(4):587-591
The synthesis and reactivity studies of 4‐hydroxy‐6‐methyl‐3‐(5‐phenyl‐2E,4E‐pentadien‐1‐oyl)‐2H‐pyran‐2‐one 2 with nucleophiles are reported. Reactions of 2 with hydrazine derivatives gave new pyrazole‐type com pounds while the reaction with ortho‐phenylenediamines yielded 1,5‐benzodiazepines. The reaction of 2 with ethylamine implies the 2H‐pyran‐2‐one ring opening and the formation of a strong conjugated compound 3. 相似文献
9.
Matthew Akerman Kate Akerman Deogratius Jaganyi Desigan Reddy 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(9):m290-m292
The reaction between [PtCl(terpy)]·2H2O (terpy is 2,2′:6′,2′′‐terpyridine) and pyrazole in the presence of two equivalents of AgClO4 in nitromethane yields the title compound, [Pt(C3H4N2)(C15H11N3)](ClO4)2·CH3NO2, as a yellow crystalline solid. Single‐crystal X‐ray diffraction shows that the dicationic platinum(II) chelate is square planar with the terpyridine ligand occupying three sites and the pyrazole ligand occupying the fourth. The torsion angle subtended by the pyrazole ring relative to the terpyridine chelate is 62.4 (6)°. Density functional theory calculations at the LANL2DZ/PBE1PBE level of theory show that in vacuo the lowest‐energy conformation has the pyrazole ligand in an orientation perpendicular to the terpyridine ligand (i.e. 90°). Seemingly, the stability gained by the formation of hydrogen bonds between the pyrazole NH group and the perchlorate anion in the solid‐state structure is sufficient for the chelate to adopt a higher‐energy conformation. 相似文献
10.
Tullio Pilati Gianluigi Casalone 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o178-o180
The title diastereoisomers, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate and methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, both C19H23N3O5, have been studied in two crystalline forms. The first form, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate–methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate (1/1), 2(S),5(S)‐C19H23N3O5·2(R),5(S)‐C19H23N3O5, contains both S,S and S,R isomers, while the second, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, 2(S),5(S)‐C19H23N3O5, is the pure S,S isomer. The S,S isomers in the two structures show very similar geometries, the maximum difference being about 15° on one torsion angle. The differences between the S,S and S,R isomers, apart from those due to the inversion of one chiral centre, are more remarkable, and are partially due to a possible rotational disorder of the 2‐(methoxycarbonyl)tetrahydropyrrole group. 相似文献
11.
Charles Pathirana Chris Sfouggatakis Venkatapuram Palaniswamy 《Magnetic resonance in chemistry : MRC》2013,51(3):184-187
During a synthesis of 5‐amino‐4‐(6‐methoxy‐2‐methylpyridin‐3‐yl)‐3‐methyl‐1H‐pyrazole‐1‐carboxamide (see Scheme 1), a side‐reaction produced 3‐amino‐4‐(6‐methoxy‐2‐methylpyridin‐3‐yl)‐5‐methyl‐1H‐pyrazole‐1‐carboxamide as a by‐product that forms an equilibrium with the target‐compound. The structure of the by‐product was elucidated by the interpretation of 1D and 2D (HMQC, HMBC) NMR data where 1H‐15 N HMBC correlations revealed the position of carbamoyl group attachment on the pyrazole. Comparison of structures of the target‐compound and the by‐product showed that the latter resulted from N‐N migration of the carbamoyl group in the target‐compound. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
12.
《Magnetic resonance in chemistry : MRC》2003,41(4):265-268
Upon irradiation with a 450 W high‐pressure mercury lamp, the CB1 cannabinoid antagonist N‐(piperidinyl)‐5‐(4‐chlorophenyl)‐1‐(2,4‐dichlorophenyl)‐4‐methyl‐1H‐pyrazole‐3‐carboxamide (SR14‐1716; 1 ) undergoes a photocyclization reaction to yield a single reaction product. This product, 2 , the structure of which is based on a pyrazolo[1,5‐f]phenanthridine ring system, was established by two‐dimensional NMR techniques (COSY, HSQC, HMBC and ROESY), and was later confirmed by single‐crystal x‐ray diffraction analysis. The crystal structure shows two independent molecules of 3 and a half molecule of the 1,2‐dichloroethane solvate. Compound 2 has reasonably high affinity for the CB1 receptor (Ki = 48.0 ± 2.7 nM ). Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
13.
Edison Castro Henry Insuasty Braulio Insuasty Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(11):1064-1068
The title compound, C18H18N4OS2, was prepared by reaction of S,S‐diethyl 2‐thenoylimidodithiocarbonate with 5‐amino‐3‐(4‐methylphenyl)‐1H‐pyrazole using microwave irradiation under solvent‐free conditions. In the molecule, the thiophene unit is disordered over two sets of atomic sites, with occupancies of 0.814 (4) and 0.186 (4), and the bonded distances provide evidence for polarization in the acylthiourea fragment and for aromatic type delocalization in the pyrazole ring. An intramolecular N—H...O hydrogen bond is present, forming an S(6) motif, and molecules are linked by N—H...O and N—H...N hydrogen bonds to form a ribbon in which centrosymmetric R22(4) rings, built from N—H...O hydrogen bonds and flanked by inversion‐related pairs of S(6) rings, alternate with centrosymmetric R22(6) rings built from N—H...N hydrogen bonds. 相似文献
14.
3‐Acyl‐4‐hydroxy‐2‐oxo‐2H‐chromen derivatives 1a‐d were condensed with (7‐hydroxy‐2‐oxo‐2H‐chromen‐4‐yl)‐acetic acid hydrazide 2 , (4‐methyl‐2‐oxo‐2H‐chromen‐7‐yloxy)‐acetic acid hydrazide 3 , and (7‐hydrazinocarbonylmethoxy‐2‐oxo‐2H‐chromen‐4‐yl)‐acetic acid hydrazide 4 , to give corresponding 3‐alkyl‐1‐[2‐(7‐hydroxy‐2‐oxo‐2H‐chromeno‐4‐yl)‐acetyl]‐1H‐chromeno[4,3‐c]pyrazole‐4‐one 5a‐d , 3‐alkyl‐1‐[2‐(4‐methyl‐2‐oxo‐2H‐chromeno‐7‐yloxy)‐acetyl]‐1H‐chromeno[4,3‐c]pyrazole‐4‐one 6a‐d , and 1‐{4‐[(3‐alkyl‐1H‐chromeno[4,3‐c]pyrazole‐4‐one‐1‐yl)‐carbonylmethyl]‐2‐oxo‐2H‐chromen‐7‐yloxy‐acetyl}‐3‐alkyl‐1H‐chromeno[4,3‐c]pyrazole‐4‐one 7a‐d. 相似文献
15.
Syntheses of New Unsymmetrical 2,5‐Disubstituted‐1,3,4‐oxadiazoles and 1,2,4‐Triazolo[3,4‐b]‐1,3,4‐thiadiazoles Bearing Thieno[2,3‐c]pyrazolo Moiety
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Shivaraj P. Patil Shrikant B. Kanawade Dinesh C. Bhavsar Prashant S. Nikam Sachin A. Gangurde Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(2):368-373
New series of (thieno[2,3‐c]pyrazolo‐5‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles 10a , 10b , 10c and (thieno[2,3‐c]pyrazol‐5‐yl)‐1,3,4‐oxadiazol‐3(2H)‐yl)ethanones 6a , 6b , 6c has been synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by multistep reaction sequence. (5‐Aryl‐1,3,4‐oxadiazol‐2‐yl)‐1H‐thieno[2,3‐c]pyrazoles 4a , 4b , 4c were also synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by cyclization with various aromatic carboxylic acids. The hydrazide 3 was obtained by reaction of thieno[2,3‐c]pyrazole‐5‐carboxylate 2 with hydrazine hydrate in good yield, and compound 2 was obtained by the reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde 1 and 2‐ethyl thioglycolate in presence of sodium alcoholate in good yield. 相似文献
16.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(10):1138-1145
This article presents the synthesis of three new 4‐thiopyrimidine derivatives obtained from ethyl 4‐methyl‐2‐phenyl‐6‐sulfanylpyrimidine‐5‐carboxylate as the starting material, namely, ethyl 4‐[(4‐chlorobenzyl)sulfanyl]‐6‐methyl‐2‐phenylpyrimidine‐5‐carboxylate, C21H19ClN2O2S, ( 2 ), {4‐[(4‐chlorobenzyl)sulfanyl]‐6‐methyl‐2‐phenylpyrimidin‐5‐yl}methanol, C19H17ClN2OS, ( 3 ), and 4‐[(4‐chlorobenzyl)sulfanyl]‐5,6‐dimethyl‐2‐phenylpyrimidine, C19H17ClN2S, ( 4 ), which vary in the substituent at the 5‐position of the pyrimidine ring. The compounds were characterized by 1H NMR, 13C NMR, IR and mass spectroscopies, and also elemental analysis. The molecular structures were further studied by single‐crystal X‐ray diffraction. Compound ( 2 ) crystallizes in the space group P with one molecule in the asymmetric unit, whereas compounds ( 3 ) and ( 4 ) crystallize in the space group P21/c with two and one molecule, respectively, in their asymmetric units. The conformation of each molecule is best defined by the dihedral angles formed between the pyrimidine ring and the planes of the two aryl substituents attached at the 2‐ and 4‐positions. The only structural difference between the three compounds is the substituent at the 5‐position of the pyrimidine ring, but they present significantly different features in the hydrogen‐bond interactions. Compound ( 2 ) displays a one‐dimensional chain formed by hydrogen bonds and the chains are further extended into a two‐dimensional network. Molecules of ( 3 ) and ( 4 ) generate one‐dimensional chains formed through intermolecular interactions. The study examines the cytotoxicity of compounds ( 3 ) and ( 4 ) against Human umbilical vein endothelial cells (HUVEC) and HeLa, K562 and CFPAC cancer cell lines. The presence of the hydroxymethyl and methyl groups in ( 3 ) and ( 4 ), respectively, offers an interesting new insight into the structures and behaviour of these derivatives. Compound ( 4 ) was found to be nontoxic against CFPAC and HUVEC; however, it shows weak activity against the HeLa and K563 cell lines. The presence of a hydroxy group in ( 3 ) significantly increases its cytotoxicity towards both, i.e. the cancer (HeLa, K562 and CFPAC) and normal (HUVEC) cell lines. 相似文献
17.
A Divergent Synthesis of Spiropyrazole Derivatives Containing Iminolactone and/or Cyclic Imide Moiety
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Eiichi Masumoto Hiroshi Maruoka Fumi Okabe Toshihiro Fujioka Kenji Yamagata 《Journal of heterocyclic chemistry》2015,52(1):48-53
An approach to spiropyrazole derivatives containing iminolactone and/or cyclic imide moiety starting from 1H‐pyrazole‐4‐acetic acid derivative is described. Hydrolysis of C‐cyanomethylated 1H‐pyrazole‐4‐acetic acid methyl ester ( 1 ), which was easily prepared from 1H‐pyrazole‐4‐acetic acid derivative by a C‐cyanomethylation, led to the C‐cyanomethylated 1H‐pyrazole‐4‐acetic acid ( 2 ). Compound 2 was reacted with ethanol in the presence of tin(IV) chloride in refluxing chloroform to give the key intermediate ethyl imidate ( 3 ). Sodium hydride‐assisted lactonization of 3 in N,N‐dimethylformamide afforded the spiropyrazole derivative containing iminolactone moiety ( 4 ). On the other hand, thermal treatment of 3 with sodium acetate in the absence of solvent caused another intramolecular cyclization to yield the spiropyrazole derivative containing cyclic imide moiety ( 6 ). 相似文献
18.
Alicja Janik Andrzej Olech Anna Stasiewicz‐Urban Katarzyna Stadnicka 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(2):o70-o75
The room‐temperature crystal structures of four new thio derivatives of N‐methylphenobarbital [systematic name: 5‐ethyl‐1‐methyl‐5‐phenylpyrimidine‐2,4,6(1H,3H,5H)‐trione], C13H14N2O3, are compared with the structure of the parent compound. The sulfur substituents in N‐methyl‐2‐thiophenobarbital [5‐ethyl‐1‐methyl‐5‐phenyl‐2‐thioxo‐1,2‐dihydropyrimidine‐4,6(3H,5H)‐dione], C13H14N2O2S, N‐methyl‐4‐thiophenobarbital [5‐ethyl‐1‐methyl‐5‐phenyl‐4‐thioxo‐3,4‐dihydropyrimidine‐2,6(1H,5H)‐dione], C13H14N2O2S, and N‐methyl‐2,4,6‐trithiophenobarbital [5‐ethyl‐1‐methyl‐5‐phenylpyrimidine‐2,4,6(1H,3H,5H)‐trithione], C13H14N2S3, preserve the heterocyclic ring puckering observed for N‐methylphenobarbital (a half‐chair conformation), whereas in N‐methyl‐2,4‐dithiophenobarbital [5‐ethyl‐1‐methyl‐5‐phenyl‐2,4‐dithioxo‐1,2,3,4‐tetrahydropyrimidine‐6(5H)‐one], C13H14N2OS2, significant flattening of the ring was detected. The number and positions of the sulfur substituents influence the packing and hydrogen‐bonding patterns of the derivatives. In the cases of the 2‐thio, 4‐thio and 2,4,6‐trithio derivatives, there is a preference for the formation of a ring motif of the R22(8) type, which is also a characteristic of N‐methylphenobarbital, whereas a C(6) chain forms in the 2,4‐dithio derivative. The preferences for hydrogen‐bond formation, which follow the sequence of acceptor position 4 > 2 > 6, confirm the differences in the nucleophilic properties of the C atoms of the heterocyclic ring and are consistent with the course of N‐methylphenobarbital thionation reactions. 相似文献
19.
Wafaa S. Hamama Hamada G. El‐Gohary Mamdouh Soliman Hanfi H. Zoorob 《Journal of heterocyclic chemistry》2012,49(3):543-554
This research work describes the synthesis and biological properties of some novel isolated or fused heterocyclic ring systems with pyrazole, for example; enaminones containing pyrazolone ring photochromic functional unit, 4‐[(4‐chlorophenylamino)methylene]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐one (3) and some analogous derivatives 4, 9, and 10, also as pyrazolo[3,4‐b]pyridine, pyrazolo[3,4‐b]quinoline, pyrazolo[3′,4′:4,5]thieno[2,3‐c]pyrazoline and pyrazolo[3,4‐c]pyrazole were synthesized and characterized. Newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, mass spectral data and quantum mechanical calculations. Selected products were tested for their antibacterial and antitumor agents. 相似文献
20.
Three sterically hindered 6‐amino‐5‐cyano‐2‐methyl‐4‐(1‐naphthyl)‐4H‐pyran‐3‐carboxylate derivatives
Vladimir N. Nesterov David J. Wiedenfeld Svitlana V. Nesterova Lucas F. Hastings 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o685-o689
In the title compounds, 2‐methoxyethyl 6‐amino‐5‐cyano‐2‐methyl‐4‐(1‐naphthyl)‐4H‐pyran‐3‐carboxylate, C21H20N2O4, (II), isopropyl 6‐amino‐5‐cyano‐2‐methyl‐4‐(1‐naphthyl)‐4H‐pyran‐3‐carboxylate, C21H20N2O3, (III), and ethyl 6‐amino‐5‐cyano‐2‐methyl‐4‐(1‐naphthyl)‐4H‐pyran‐3‐carboxylate, C20H18N2O3, (IV), the heterocyclic pyran ring adopts a flattened boat conformation. In (II) and (III), the carbonyl group and a double bond of the heterocyclic ring are mutually anti, but in (IV) they are mutually syn. The ester O atoms in (II) and (III) and the carbonyl O atom in (IV) participate in intramolecular C—H...O contacts to form six‐membered rings. The dihedral angles between the naphthalene substituent and the closest four atoms of the heterocyclic ring are 73.3 (1), 71.0 (1) and 74.3 (1)° for (II)–(IV), respectively. In all three structures, only one H atom of the NH2 group takes part in N—H...O [in (II) and (III)] or N—H...N [in (IV)] intermolecular hydrogen bonds, and chains [in (II) and (III)] or dimers [in (IV)] are formed. In (II), weak intermolecular C—H...O and C—H...N hydrogen bonds, and in (III) intermolecular C—H...O hydrogen bonds link the chains into ladders along the a axis. 相似文献