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1.
Kouzou Matsumoto Dr. Takuya Inagaki Tatsuo Nehira Dr. Masaki Kannami Dr. Daisuke Inokuchi Hiroyuki Kurata Dr. Takeshi Kawase Dr. Gennaro Pescitelli Dr. Masaji Oda Prof. Dr. 《化学:亚洲杂志》2007,2(8):1031-1036
The title compound, a prototypical chiral molecule based on a tetraarylmethane framework, has been synthesized in five steps from (2‐pyridyl)‐(3‐pyridyl)ketone. X‐ray crystallographic analysis revealed the tetraarylmethane framework of the molecule but did not determine the positions of the nitrogen atoms because the crystal is a racemic compound and the aryl groups are disordered in the crystal. The optical resolution of the title compound was achieved by chiral HPLC with a Chiralcel OD column. The CD spectra of the two fractions in acetonitrile exhibited opposite signs as expected for a pair of enantiomers. Their CD spectra are changed in 2 M HCl due to protonation. The calculated CD curve for the target molecule based on time‐dependent density functional theory (TDDFT) reproduces the experimental result very well, thus suggesting that the first eluted fraction is the R isomer in terms of absolute configuration. 相似文献
2.
The reactions of 1‐formyl‐3‐methoxycarbonylazulene ( 1 ) with acetophenones 3a‐e gave 1‐(3‐aryl‐3‐oxopropenyl)‐3‐methoxycarbonylazulenes 4a‐e which reacted with malononitrile in the presence of sodium methoxide to afford 1‐(2‐aryl‐4‐pyridyl)‐3‐methoxycarbonylazulenes 9a‐d , except for 4′‐nitro‐substituted compounds. Heating of the compounds 9a‐d in 100% phosphoric acid yielded 1‐(2‐aryl‐4‐pyridyl)azulenes 10a‐d . In a similar manner, 1‐(4‐aryl‐2‐pyridyl)azulenes 12a‐1 and 1‐[4‐(2‐furyl)‐ and 4‐(2‐thienyl)‐2‐pyridyl)]azulenes 14a,b were obtained. 相似文献
3.
Katie Donnelly John F. Gallagher Alan J. Lough 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(6):o335-o340
The three title isomers, 4‐, (I), 3‐, (II), and 2‐fluoro‐N′‐(4‐pyridyl)benzamide, (III), all C12H9FN2O, crystallize in the P21/c space group (No. 14) with similar unit‐cell parameters and are isomorphous and isostructural at the primary hydrogen‐bonding level. An intramolecular C—H...O=C interaction is present in all three isomers [C...O = 2.8681 (17)–2.884 (2) Å and C—H...O117–118°], with an additional N—H...F [N...F = 2.7544 (15) Å] interaction in (III). Intermolecular amide–pyridine N—H...N hydrogen bonds link molecules into one‐dimensional zigzag chains [graph set C(6)] along the [010] direction as the primary hydrogen bond [N...N = 3.022 (2), 3.049 (2) and 3.0213 (17) Å]. These are augmented in (I) by C—H...π(arene) and cyclic C—F...π(arene) contacts about inversion centres, in (II) by C—F...F—C interactions [C...F = 3.037 (2) Å] and weaker C—H...π(arene)/C—H...F contacts, and in (III) by C—H...π(arene) and C=O...O=C interactions, linking the alternating chains into two‐dimensional sheets. Typical amide N—H...O=C hydrogen bonds [as C(4) chains] are not present [N...O = 3.438 (2) Å in (I), 3.562 (2) Å in (II) and 3.7854 (16) Å in (III)]; the C=O group is effectively shielded and only participates in weaker interactions/contacts. This series is unusual as the three isomers are isomorphous (having similar unit‐cell parameters, packing and alignment), but they differ in their interactions and contacts at the secondary level. 相似文献
4.
《Journal of heterocyclic chemistry》2018,55(3):743-749
A series of 2‐substitued‐(3‐pyridyl)‐quinazolinone derivatives were synthesized, characterized, and evaluated for bacteriostatic activity against three species of phytopathogenic bacteria (Xanthomonas oryzae pv. oryzae, Xoo, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri, Xac). Biological evaluation showed that compounds 4b , 4g , 4h , 4l , and 4m exhibited higher antibacterial activity than bismerthiazol, the positive control, under conditions. In particular, compounds 4l and 4m exhibited significant bacteriostatic activity against Xac. 相似文献
5.
San‐nu Zhou Li‐xue Zhang An‐jiang Zhang Ji‐shun Sheng Hai‐le Zhang 《Journal of heterocyclic chemistry》2007,44(5):1019-1022
6.
S. Sukdolak S. Soluji N. Manojlovi N. Vukovi L. J. Krsti 《Journal of heterocyclic chemistry》2004,41(4):593-596
3‐Acetyl‐4‐hydroxy‐chromen‐2‐one ( 1 ) was brominated with phenyltrimethylammonium tribromide to afford 3‐(2‐bromoacetyl)‐4‐hydroxy‐chromen‐2‐one ( 2 ) whose reactions with thiourea, thioacetamide and ammonium dithiocarbamate gave respectively 3‐(2‐amino‐thiazol‐4‐yl)‐4‐hydroxy‐, 4‐hydroxy‐3‐(2‐phenyl‐thiazol‐4‐yl)‐ and 4‐hydroxy‐3‐(2‐mercapto‐thiazol‐4‐yl)chromen‐2‐one. In a similar manner, com pound 2 was treated with four 1‐substituted‐2‐thioureas and thiobenzamide to give the corresponding 4‐hydroxy‐3‐(thiazol‐4‐yl)‐chromen‐2‐one derivatives. 相似文献
7.
Tuncay TuncÛ Musa Sar Rahmi Yagbasan Habibe Tezcan Ertan SÛahin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o192-o193
Molecules of the title compound (alternative name p‐methoxybenzaldehyde 2‐pyridylhydrazone), C13H13N3O, adopt an E configuration about the azomethine C=N double bond. Molecules are almost planar, the dihedral angle between the pyridine and methoxyphenyl rings being only 6.19 (12)°. Pairwise N—H⃛N hydrogen bonds [R(8) in graph‐set notation] link centrosymmetrically related molecules into discrete pairs. 相似文献
8.
9.
Muhammad Altaf Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(9):o441-o445
The title compounds, C10H9N5O·H2O (L1·H2O) and C16H12N6O (L2), were synthesized by solvent‐free aldol condensation at room temperature. L1, prepared by grinding picolinaldehyde with 2,3‐diamino‐3‐isocyanoacrylonitrile in a 1:1 molar ratio, crystallized as a monohydrate. L2 was prepared by grinding picolinaldehyde with 2,3‐diamino‐3‐isocyanoacrylonitrile in a 2:1 molar ratio. By varying the conditions of crystallization it was possible to obtain two polymorphs, viz. L2‐I and L2‐II; both crystallized in the monoclinic space group P21/c. They differ in the orientation of one pyridine ring with respect to the plane of the imidazole ring. In L2‐I, this ring is oriented towards and above the imidazole ring, while in L2‐II it is rotated away from and below the imidazole ring. In all three molecules, there is a short intramolecular N—H...N contact inherent to the planarity of the systems. In L1·H2O, this involves an amino H atom and the C=N N atom, while in L2 it involves an amino H atom and an imidazole N atom. In the crystal structure of L1·H2O, there are N—H...O and O—H...O intermolecular hydrogen bonds which link the molecules to form two‐dimensional networks which stack along [001]. These networks are further linked via intermolecular N—H...N(cyano) hydrogen bonds to form an extended three‐dimensional network. In the crystal structure of L2‐I, symmetry‐related molecules are linked via N—H...N hydrogen bonds, leading to the formation of dimers centred about inversion centres. These dimers are further linked via N—H...O hydrogen bonds involving the amide group, also centred about inversion centres, to form a one‐dimensional arrangement propagating in [100]. In the crystal structure of L2‐II, the presence of intermolecular N—H...O hydrogen bonds involving the amide group results in the formation of dimers centred about inversion centres. These are linked via N—H...N hydrogen bonds involving the second amide H atom and the cyano N atom, to form two‐dimensional networks in the bc plane. In L2‐I and L2‐II, C—H...π and π–π interactions are also present. 相似文献
10.
Satish S. More Akula Raghunadh Ramanathan Shankar Navin B. Patel Dinesh S. Bhalerao Unniaran K. Syam Kumar 《Helvetica chimica acta》2014,97(3):404-413
The first total synthesis of the α‐oxo amide‐based natural product, N‐(3‐guanidinopropyl)‐2‐(4‐hydroxyphenyl)‐2‐oxoacetamide ( 3 ), isolated from aqueous extracts of hydroid Campanularia sp., has been achieved. The α‐oxo amide 12 , prepared via the oxidative amidation of 1‐[4‐(benzyloxy)phenyl]‐2,2‐dibromoethanone ( 9a ) with 4‐{[(tert‐butyl)(dimethyl)silyl]oxy}butan‐1‐amine ( 10a ), has been used as the key intermediate in the total synthesis of 3 as HBr salt. On the way, an expeditious total synthesis of polyandrocarpamide C ( 2c ), isolated from marine ascidian Polyandrocarpa sp., was carried out in four steps. 相似文献
11.
Volodimir D. Vreshch Andrey B. Lysenko Harald Krautscheid Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):m443-m447
In bis[1‐(3‐pyridyl)butane‐1,3‐dionato]copper(II) (the Cu atom occupies a centre of inversion), [Cu(C9H8NO2)2], (I), and bis[1‐(4‐pyridyl)butane‐1,3‐dionato]copper(II) methanol solvate, [Cu(C9H8NO2)2]·CH3OH, (II), the O,O′‐chelating diketonate ligands support square‐planar coordination of the metal ions [Cu—O = 1.948 (1)–1.965 (1) Å]. Weaker Cu⋯N interactions [2.405 (2)–2.499 (2) Å], at both axial sides, occur between symmetry‐related bis(1‐pyridylbutane‐1,3‐dionato)copper(II) molecules. This causes their self‐organization into two‐dimensional square‐grid frameworks, with uniform [6.48 Å for (I)] or alternating [4.72 and 6.66 Å for (II)] interlayer separations. Guest methanol molecules in (II) reside between the distal layers and form weak hydrogen bonds to coordinated O atoms [O⋯O = 3.018 (4) Å]. 相似文献
12.
Functionalized 5‐(arylselanyl)‐2‐(arylsulfanyl)benzoates were prepared by [3+3] cyclocondensation of 3‐(arylsulfanyl)‐1‐(silyloxy)buta‐1,3‐dienes with 2‐(arylselanyl)‐3‐(silyloxy)‐alk‐2‐en‐1‐ones. 相似文献
13.
New 3‐aroyl‐4‐(3‐chromonyl)‐2‐pyrazolines have been synthesized by the reaction of 3‐(3‐aryl‐3‐oxo‐propenyl)chromen‐4‐ones and diazomethane. Some of these 2‐pyrazolines have also been N‐acylated with a mixture of anhydrous pyridine and acetic anhydride or propionic anhydride. Structures of all new compounds have been elucidated by elemental analyses, mass spectrometry, ir and nmr spectroscopic measurements. 相似文献
14.
Synthesis of 9‐[2‐(2‐hydroxymethyl‐2‐methyl‐, ‐(2‐acetoxymethyl‐2‐methyl‐, ‐(2,2‐di(hydroxymethyl)‐, and ‐(2,2‐di(acetoxymethyl)‐1,3‐dioxan‐5‐yl)ethyl] derivatives of guanine and 2‐aminopurine, 2–9 , has been accomplished in seven to eight step sequences from readily available 1‐(tert‐butyldiphenylsilyloxy)‐acetone, 1,3‐di(tert‐butyldiphenylsilyloxy)acetone, and the diol 10 . Formation of cyclic ketals 11 and 12 was carried out successfully under an acidic condition using a catalytic amount of methanesulfonic acid along with excess anhydrous copper(II) sulfate in toluene. Subsequent reactions of desilylation, acetylation, hydrogenolysis, and bromination afforded the key intermediates 19 and 20 , which were coupled with 2‐amino‐6‐chloropurine to produce the purine compounds 21 and 22 in good yields. Guanine derivatives 2–5 were obtained from 21 and 22 by hydrolysis and acetylation, while the dechlorination and hydrolysis of 21 and 22 yielded the 2‐aminopurine compounds 6–9 . 相似文献
15.
Nilo Zanatta Elizandra C. S. Lopes Leonardo Fantinel Helio G. Bonacorso Marcos A. P. Martins 《Journal of heterocyclic chemistry》2002,39(5):943-947
The synthesis of a novel series of twelve 4‐(trihalomethyl)dipyrimidin‐2‐ylamines, from the cyclo‐condensation reaction of 4‐(trichloromethyl)‐2‐guanidinopyrimidine, with β‐alkoxyvinyl trihalomethyl ketones, of general formula: X3C‐C(O)‐C(R2)=C(R1)‐OR, where: X = F, Cl; R = Me, Et, ‐(CH2)2‐, ‐(CH2)3‐; R1 = H, Me; R2 = H, Me, ‐(CH2)2‐, ‐(CH2)3‐, is reported. The reactions were carried out in acetonitrile under reflux for 16 hours, leading to the dipyrimidin‐2‐ylamines in 65‐90% yield. Depending on the substituents of the vinyl ketone, tetrahydropyrimidines or aromatic pyrimidine rings were obtained from the cyclization reaction. When X = Cl, elimination of the trichloromethyl group was observed during the cyclization step. The structure of 4‐(trihalomethyl)dipyrimidin‐2‐ylamines was studied in detail by 1H‐, 13C‐ and 2D‐nmr spectroscopy. 相似文献
16.
Diastereoselective addition of hypophosphorous acid to N‐(R)‐α‐methylbenzyl‐substituted schiff bases
The addition of hypophosphorous acid to an azomethine bond of N‐(R)‐α‐methylbenzyl Schiff bases of a variety of aldehydes led to the formation of N‐(R)‐α‐methylbenzylamino‐(S)‐methanephosphonous acids in 100% diastereoselectivity. This fact allows us to suggest the probable mechanism of the Strecker‐like reaction between hypophosphorous acid, an aldehyde, and (R)‐α‐methylbenzylamine. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:35–37, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20406 相似文献
17.
Kadri G. Ozokan Mustafa K. Gumus Seniz Kaban 《Journal of heterocyclic chemistry》2008,45(6):1831-1834
18.
The [4+2] cycloaddition of 3‐(arylsulfanyl)‐1‐(trimethylsilyloxy)buta‐1,3‐dienes with dimethyl penta‐2,3‐dienedioate provides a convenient and regioselective approach to a variety of 4‐(arylsulfanyl)‐2‐hydroxyhomophthalates. 相似文献
19.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):830-832
The structure of the title compound, C9H8N4, comprises non‐planar molecules that associate via pyrimidine N—H?N dimer R(8) hydrogen‐bonding associations [N?N 3.1870 (17) Å] and form linear hydrogen‐bonded chains via a pyrimidine N—H?N(pyridyl) interaction [N?N 3.0295 (19) Å]. The dihedral angle between the two rings is 24.57 (5)°. The structure of the 1:1 adduct with 4‐aminobenzoic acid, C9H8N4·C7H7NO2, exhibits a hydrogen‐bonding network involving COOH?N(pyridyl) [O?N 2.6406 (17) Å], pyrimidine N—H?N [N?N 3.0737 (19) and 3.1755 (18) Å] and acid N—H?O interactions [N?O 3.0609 (17) and 2.981 (2) Å]. The dihedral angle between the two linked rings of the base is 38.49 (6)° and the carboxylic acid group binds to the stronger base group in contrast to the (less basic) complementary hydrogen‐bonding site. 相似文献
20.
Diana C. G. A. Pinto Artur M. S. Silva Jos A. S. Cavaleiro 《Journal of heterocyclic chemistry》2000,37(6):1629-1634
The 3‐(2‐benzyloxy‐6‐hydroxyphenyl)‐5‐(methyl, phenyl or styryl)pyrazoles were prepared from the reaction of 2‐(methyl, phenyl or styryl)chromones with methylhydrazine. The structure of these compounds has been determined by several nmr techniques, and the reaction mechanism is discussed. 相似文献