共查询到20条相似文献,搜索用时 31 毫秒
1.
WANG Nong LI Jing-Ping PU Yan-Ling 《结构化学》2007,26(5):547-550
A new Schiff base compound, 2-hydroxybenzoic acid [1-(3,5-dibromo-2-hydroxy- phenyl) methylidene]hydrazide methanol (C14H10Br2N2O3·CH3OH), has been synthesized by the condensation of equimolar 3,5-dibromosalicylaldehyde and 2-hydroxybenzoic acid hydrazide in a methanol solution. The compound was characterized by elemental analysis, IR spectra, and single- crystal X-ray diffraction. The compound consists of a Schiff base moiety 2-hydroxybenzoic acid [1-(3,5-dibromo-2-hydroxyphenyl)methylidene]hydrazide and a lattice methanol molecule. The crystal belongs to the monoclinic system, space group P21/n with a = 7.183(1), b = 15.673(2), c = 15.001(2) , β = 98.345(2)o, Z = 4, V = 1670.9(4) 3, Dc = 1.773 g/cm3, Mr = 446.10, λ(MoKα) = 0.71073 , μ = 4.872 mm-1, F(000) = 880, R = 0.0458 and wR = 0.0963. A total of 3445 unique reflections were collected, of which 2236 with I > 2σ(I) were observed. As expected, the molecule adopts a trans configuration about the C=N double bond. The two benzene rings are nearly coplanar (mean deviation from the combined plane is 0.061(4) ), with the dihedral angle of 7.9(3)o. The preliminary biological tests show that the compound has moderate antibacterial activities. 相似文献
2.
Mara Gutirrez-Snchez Aurelio Romero-Castro Jos Correa-Basurto Martha Cecilia Rosales-Hernndez Itzia Irene Padilla-Martínez Jessica Elena Mendieta-Wejebe 《Molecules (Basel, Switzerland)》2021,26(22)
Compound 5-{[(2E)-3-bromo-3-carboxyprop-2-enoyl]amino}-2-hydroxybenzoic acid (C1), a new 5-aminosalicylic acid (5-ASA) derivative, has proven to be an antioxidant in vitro and an anti-inflammatory agent in mice. The in vivo inhibition of myeloperoxidase was comparable to that of indomethacin. The aim of this study was to take another step in the preclinical evaluation of C1 by examining acute toxicity with the up-and-down OECD method and pharmacokinetic profiles by administration of the compound to Wistar rats through intravenous (i.v.), oral (p.o.), and intraperitoneal (i.p.) routes. According to the Globally Harmonized System, C1 belongs to categories 4 and 5 for the i.p. and p.o. routes, respectively. An RP-HPLC method for C1 quantification in plasma was successfully validated. Regarding the pharmacokinetic profile, the elimination half-life was approximately 0.9 h with a clearance of 24 mL/min after i.v. administration of C1 (50 mg/kg). After p.o. administration (50 mg/kg), the maximum plasma concentration was reached at 33 min, the oral bioavailability was about 77%, and the compound was amply distributed to all tissues evaluated. Therefore, C1 administered p.o. in rats is suitable for reaching the colon where it can exert its effect, suggesting an important advantage over 5-ASA and indomethacin in treating ulcerative colitis and Crohn’s disease. 相似文献
3.
A diamine was synthesized by two successive reactions.Nucleophilic reaction of 4-hydroxybenzoic acid with terephthaloyl chloride yielded terephthaloyl bis(4-oxybenzoic) acid.Then reaction of this compound with 1,8-diamino-3,6- dioxaoctane via Yamazaki method resulted in preparation of diamine named terephthalic acid bis(4-{2-[2-(2-amino ethoxy)ethoxy]ethyl carbamoyl}phenyl) ester.After fully characterization it was used to prepare new polyimides through polycondensation with different dianhydrides using trimethylchlorosilane.Characterization of polymers was achieved by common methods and their physical properties including inherent viscosity,thermal behavior,thermal stability,crystallinity and solubility were studied.Prepared polyimides showed improved solubility and good thermal stability. 相似文献
4.
B. E. Ezema L. E. S. Akpanisi C. G. Ezema A. E. Onoabedje 《Journal of heterocyclic chemistry》2015,52(5):1411-1414
Ethyl 7‐(2‐ethoxy‐2‐oxoethyl)‐3‐phenyl‐[1–3]triazolo[5,1‐c][1,2,4]triazine‐6‐carboxylate (the parent compound) was synthesized by reaction of 4‐phenyl–1H‐1,2,3‐triazole‐5‐diazonium chloride with diethyl‐2‐oxopropane‐1,3‐dicarboxylate at cooling for 2 h. During the reaction of the parent compound with p‐toluenesulphonyl azide in triethylamine, the Dimroth rearrangement occurred to give the tricyclic compound. 相似文献
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Fukuji Higashi Koichi Kubota Misuzu Sekizuka Morio Higashi 《Journal of polymer science. Part A, Polymer chemistry》1981,19(11):2681-2687
Polyaryl esters of moderate molecular weights were prepared by the direct polycondensation reaction of hydroxybenzoic acids and its derivatives with hexachlorocyclotriphosphatriazene (also known as phosphonitrilic chloride trimer, PNC) as a condensing agent in pyridine. Copolymerization of p-hydroxybenzoic acid with several hydroxybenzic acid derivatives was carried out to improve the processability of the polymer of p-hydroxybenzoic acid, which yields fusible and soluble copolymers of high inherent viscosities. Polymer solubility and thermal behavior were examined. 相似文献
7.
A diacid (TOBA) containing an ester group was synthesized by reaction of terephthaloyl chloride with 4-hydroxybenzoic acid. Reaction of the obtained diacid with thionyl chloride resulted in preparation of the related diacid chloride (TOBC). Nucleophilic substitution reaction of 4-aminophenol and also 5-amino-l-naphthol with the prepared diacid chloride afforded two aromatic diols containing ester and amide groups, respectively. Aromatic and semi-aromatic poly(ester-amide-urethane)s were prepared via addition polymerization of different diisocyanates with novel diols. The prepared polyurethanes showed improved thermal stability. 相似文献
8.
培养南海红树林内源真菌Fusarium sp. ZZF60产新型蒽醌衍生物 总被引:1,自引:0,他引:1
通过人工发酵培养,从南海红树林内源真菌Fusarium sp.ZZF60的培养液中分离得到:1种新蒽醌衍生物,6,8-二甲氧基-1-甲基-2-(3-氧丁基)蒽醌(1),以及5种已知化合物:7-羟基-3-(4-甲氧基苯基)苯并-γ-吡喃酮(2),2,4-二羟基-6-[(1′E,3′E)-1′,3′-戊二烯基]苯甲醛(3),(E)-4-羟基肉桂酸甲酯(4),4-(4-羟基苯基)-2-丁醇(5),4-羟基苯甲酸(6)。它们的结构通过MS、NMR等波谱分析推导确定。初步药理活性显示,化合物1抑制体外培养人喉癌细胞Hep2和人肝癌细胞HepG2的IC50分别为16和23μmol/L。 相似文献
9.
研究了由未端化支化聚酰胺、交联剂(MBHP)和光酸产生剂(PTMA)所组成的三元负型光敏聚合物体系.其中,不对称ABB′型单体4-(2,4-二氨基苯氧基)苯甲酸3在亚磷酸三苯酯(TPP)和吡啶(Py)的存在下,通过缩合聚合得到支化聚酰胺a,由其1H-NMR数据计算得支化度(DB)为0.36.接着用肉桂酰氯对支化聚酰胺进行末端化.采用IR,1H-NMR,GPC,TG/DTA对支化聚酰胺和末端化支化聚酰胺b的结构和性能进行了表征.由85wt%末端化支化聚酰胺b、10wt%交联剂(MBHP)和5wt%光酸产生剂(PTMA)所组成的光敏聚合物体系,在100℃预烘10min,采用436nm(g-line)紫外光曝光,随后在25℃于二甲基甲酰胺中显影10s,用水漂洗,110℃后烘3min后,得到负型图案,边界清晰且分辨率达40μm. 相似文献
10.
以对羟基苯甲酸为原料,首次合成(Z)-3-丁烯基-5-羟基苯酞.发现芳环上的甲胺甲酸基中氮原子的诱导作用是关键步骤,使甲胺甲酸基邻位选择性理化,从而在芳环上定向引入甲酸基. 相似文献
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The structures of benzoic acid (C6H5COOH) and 2-hydroxybenzoic acid (C6H4OHCOOH) have been determined in the gas phase by electron diffraction using results from quantum chemical calculations to inform restraints used on the structural parameters. Theoretical methods (HF and MP2/6-311+G(d,p)) predict two conformers for benzoic acid, one which is 25.0 kJ mol(-1) (MP2) lower in energy than the other. In the low-energy form, the carboxyl group is coplanar with the phenyl ring and the O-H group eclipses the C=O bond. Theoretical calculations (HF and MP2/6-311+G(d,p)) carried out for 2-hydroxybenzoic acid gave evidence for seven stable conformers but one low-energy form (11.7 kJ mol(-1) lower in energy (MP2)) which again has the carboxyl group coplanar with the phenyl ring, the O-H of the carboxyl group eclipsing the C=O bond and the C=O of the carboxyl group oriented toward the O-H group of the phenyl ring. The effects of internal hydrogen bonding in 2-hydroxybenzoic acid can be clearly observed by comparison of pertinent structural parameters between the two compounds. These differences for 2-hydroxybenzoic acid include a shorter exocyclic C-C bond, a lengthening of the ring C-C bond between the substituents, and a shortening of the carboxylic single C-O bond. 相似文献
13.
Three new aromatic diester–dicarboxylic acids containing furan rings, namely, benzofuro[2,3-b]benzofuran-2,9-dicarboxyl-bis-phenyl ester-4,4′-dicarboxylic acid, benzofuro[2,3-b]benzofuran-2,9-dicarboxyl-bis-phenyl ester-3,3′-dicarboxylic acid and benzofuro[2,3-b]benzofuran-2,9-dicarboxyl-bis-naphthyl ester-2,2′-dicarboxylic acid were synthesized by the reaction of benzofuro[2,3-b]benzofuran-2,9-dicarbonyl chloride with 4-hydroxybenzoic acid, 3-hydroxybenzoic acid and 3-hydroxy-naphthalene-2-carboxylic acid, respectively. Diester–dicarboxylic acids were characterized by FT-IR and NMR spectroscopy and elemental analyses. Then, these monomers were converted to aromatic copoly(ester–amide)s by their reaction with various aromatic diamines via the direct polycondensation. These polymers were characterized by viscosity measurements, solubility tests, FT-IR, Ultraviolet and 1H-NMR spectroscopy and thermogravimetry. The polymers with inherent viscosities in the range of 0.16–0.37 dl/g in dimethyl sulfoxide at 30 °C were obtained in high yield. Most of them dissolved readily at room temperature in polar solvents. The synthesized copoly(ester–amide)s possessed glass-transition temperatures from 210–255 °C. The copoly(ester–amide)s exhibited excellent thermal stabilities and had 10% weight loss at temperature above 295 °C under nitrogen atmosphere. 相似文献
14.
Copolyesters of 4-hydroxybenzoic acid were prepared by thermal polycondensation of 4-acetoxybenzoic acid with various acetylated comonomers, such as 4-mercaptobenzoic acid, 3-hydroxybenzoic acid, N-(4-carboxyphenyl)4-hydroxyphthalimide or hydroquinone in combination with 1,12-dodecane bistrimellitimide. The copolyesters were characterized by elemental analyses, inherent viscosities, 1H- or 13C NMR spectroscopy, DSC-measurements, WAXS-measurements at temperatures between 25 and 425°C, microscopic observation, thermomechanical and thermogravimetrical analyses. Copolyesters containing 4-mercaptobenzoic acid or N-(4-carboxyphenyl)4-hydroxyphthalimide possess a reversible first order phase transition which represent a change of modifications and not a melting process. Both classes of copolyesters adopt the same kind of high temperature modification as poly(4-hydroxybenzoate), namely a pseudo-hexagonal chain packing. In contrast, copolyesters of 3-hydroxybenzoic acid or copoly(ester imide)s with aliphatic spacer containing more than 50% 4-hydroxybenzoic acid form a nematic phase over a broad temperature range. However, in the case of copolyesters derived from 3- and 4-hydroxybenzoic acid the homogeneous nematic melt is thermodynamically unstable and gradually turns into a heterogeneous more or less crystalline material with blocks of 4-hydroxybenzoate units. 相似文献
15.
A new copper(Ⅱ) compound has been prepared and fully characterized by elemen-tal analysis,IR,TG and single-crystal X-ray diffraction.The compound [Cu(4-hba)2(inta)(H2O)]·H2O (4-hba=4-hydroxybenzoic acid,inta=isonicotinamide) 1 crystallizes in the monoclinic system,space group P21/c with a=7.590(5),b=11.027(5),c=23.761(5),β=102.5740(10)o,V=1974.1(16) 3,Mr=991.84,Z=2,Dc=1.669 g/cm3,F(000)=1020,μ=1.166 mm-1,R=0.0353 and wR=0.0604 for 3166 observed reflections (I 2σ(I)).In compound 1,the copper cation is penta-coordinated with two carboxylate oxygen atoms from two different 4-hba ligands,two oxygen atoms from two coordinated water molecules and one nitrogen atom from inta ligand,showing a slightly distorted square-pyramidal geometry. 相似文献
16.
Two oxime-cyclophosphazenes were prepared from hexakis(4-formylphenoxy)cyclotriphosphazene (2) and hexakis(4-acetylphenoxy)cyclotriphosphazene (7). The reactions of these oximes with benzyl chloride, benzenesulfanoyl chloride, benzoyl chloride, 4-methoxybenzoyl chloride and 2-chlorobenzoyl chloride were studied. Hexa and pentasubstituted compounds were obtained from the reaction of hexakis(4-[(hydroxyimino)methyl]phenoxy)cyclotriphosphazene (3) with benzyl chloride (4) and benzoyl chloride, respectively. However, the oxime groups on 3 rearranged to nitrile (5) in the reaction of 3 with benzenesulfanoyl chloride and 1-napthalenesulfanoyl chloride. Hexasubstituted compounds were also obtained from the reactions of hexakis(4-[(1)-N-hydroxyethaneimidoyl]phenoxy)cyclotriphosphazene (8) with benzoyl chloride (10), 4-methoxybenzoyl chloride (11) and 2-chlorobenzoyl chloride (12). A trisubstituted compound was obtained from the reaction of 8 with benzyl chloride (9). All the products were generally obtained in high yields. Pure and defined products could not be obtained from the reaction of 3 with 4-methoxybenzoyl chloride and 2-chlorobenzoyl chloride. The structures of the compounds were defined by elemental analysis, IR, 1H, 13C and 31P NMR spectroscopy. 相似文献
17.
2-(2-Arylethyl)-1-memylimidazoles 3 could be prepared by different methods. The best method was the Wittig reaction of aryltriphenylphosphonium chloride 8 with 2-formyl-1-methylimidazole to give compound 6 . Reduction of compound 6 with Raney nickel gave compound 3 . 相似文献
18.
In the isolation of the constituents of Houttuyniae cordata, ten pure compounds including 1,3,5-tridecanoylbenzene (1), caryophyllene oxide (2), several sterones (3-6) and sesamin (7), plus long-chain alcohol mixture, a steroidal mixture and 4-hydroxybenzoic acid methyl ester (8), vomifoliol (9) [or Blumenol A], quercetin-3-O-β-L-rhamnoside (10), were isolated from the aerial parts of H cordata. Their structures were determined by spectral analysis. Among them, compound 1 is for the first time isolated from nature. We describe here the spectral analysis of 1, and the X-ray determination of the relative stereochemistry of vomifoliol (9). 相似文献
19.
6-Chloro-2-diethylaminoethyl-3(2H)-pyridazinone was synthesized by the reaction of 6-chloro-3(2H)-pyridazinone and 2-diethylamionethyl chloride reaction in methylbenzene.Then the structure was characterized by means of ^1H NMR,IR,UV.By the method of ab initio HF and density functional theory(DFT) BeLYP,the geometric structures of the reagent intermediate,the product and its isomer were optimized and their total energies were calculated,The properties for the frontier molecular orbitals and the rules for energy distribution were analyzed systematically.It was shown that the energy of the nitrogen alkyl compound is lower than that of the oxy alkyl compound and the former is stable than the latter.This result is in accordance with the fact that 6-chloro-2-diethylaminoethyl-3(2H)-pyridazinone is synthesized by the reaction of 6-chloride-2-diethylaminoethyl-3(2H)-pyridazinone and 2-diethylaminoethyl chloride. 相似文献
20.
The hydrogen-isotope exchange reaction (T-for-H exchange reaction) between HTO vapor and an aromatic compound having two different
kinds of functional groups has been observed at several temperatures. The rate constant (k) for each functional group in the T-for-H exchange reaction was obtained by using both theA″-McKay plot method and the data observed. Comparing thesek with each other has led to the following four conclusions in the T-for-H exchange reaction. (1) The reactivity of both the
COOH and OH groups increases with a rise in temperature. (2) As to the degree of the effect of the COOH group on the reactivity
of monosubstituted phenols, the degree inp-hydroxybenzoic acid is greater than that inm-hydroxybenzoic acid. (3) The HAMMETT rule is useful for estimating the reactivity of a certain aromatic compound. (4) TheA″-McKay plot method is also useful not only investigating the reactivity of the compounds having one kind of functional group, but
also doing the reactivity of the compounds having two different kinds of functional groups. 相似文献