4-(5-Arylvinyl-2-oxazolyl)- and 4-(5-arylbutadienyl-2-oxazolyl)-naphthalic anhydrides

4-(5-Arylvinyl-2-oxazolyl)- and 4-(5-arylbutadienyl-2-oxazolyl)naphthalic anhydrides were synthesized by a phosphonate modification of the Wittig reaction from 4-(5-bromomethyl-2-oxazolyl)naphthalic anhydride. The structures of the aryl radicals and the steric hindrance created by some of them have a substantial effect on the absorption and luminescence of these compounds in solution. The introduction of each of the vinylene groups between the aryl and heterocyclic radicals causes approximately identical shifts in the spectra, but the Stokesian shift increases. These effects are reinforced considerably under the influence of electron-donor substituents in the aryl radical. The luminescence maxima of the investigated substances range from 515 to 710 nm, and the absolute quantum yields range from 0.12 to 0.51.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 611–613, May, 1977.     

4-(5-aryl-2-oxazolyl)phthalic anhydrides

4-(5-Aryl-2-oxazolyl)-substituted phthalic anhydrides were synthesized from 4-chloroformylphthalic anhydride and various -aminomethyl aryl ketones. The spectral-luminescence properties of solutions of the products in toluene and 5% NaOH solution were investigated. It is shown that the introduction of substituents with different electronic natures in the 5-phenyl ring of 4-(5-phenyl-2-oxazolyl) phthalic anhydride has a significant effect on the spectral-luminescence characteristics of the synthesized compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 35–37, January, 1979.     

2-(5-甲基-2-苯基-噁唑基)乙醇的合成

2-(5-甲基-2-苯基-噁唑基)乙醇的合成;Dakin-West反应;还原     

Anhydrides and phenylimides of 4-(5-aryl-2-oxazolyl)naphthalic acids

A number of 4-(5-aryl-2-oxazolyl)naphthalic anhydrides were obtained by condensation of 4-chloroformylnaphthalic anhydride with -aminomethyl aryl ketones and subsequent cyclization of the resulting amides; N-phenylimides were obtained from the anhydrides by reaction with aniline. The relationship between the structures of the substances obtained and their UV and luminescence spectra was investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1331–1333, October, 1973.     

4-(5-aryl-2-oxazolyl)benzenesulfonic acid derivatives containing a dimethylamino group

Condensation of 4-chlorosulfonyl- and 4-fluorosulfonyl-benzoyl chlorides with p-dimethylamino--aminoacetophenone followed by cyclodehydration of the resulting amides leads to the formation of 4-(5-dimethylaminophenyl-2-oxazolyl)benzenesulfonyl halides, and the corresponding sulfonic ester, sulfomorpholide, sulfonamide, and sodium salt are synthesized from them. The spectral and luminescence properties of the compounds synthesized have been studied in toluene, ethanol, and DMF. The ability of the sulfonyl group to transmit the electronic effects of the substituents on it to the overall molecular -electron system of 2,5-diaryloxazole has been demonstrated. Salvation fluorochromia has been detected in polar solvents. In some of the compounds studied the Stokes shift exceeds 200 nm.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 234–237, February, 1993.     

The structures of 2-(4,5-dihydro-5-aryl-3-isoxazolyl)-1-arylethanone oximes. An unusual behaviour in its 1H-NMR and mass spectra

The reaction of dibenzalacetones substituted on the aromatic ring with hydroxylamine hydrochloride and potassium hydroxide in refluxing ethanol affords several compounds. Herein, we report the structures and spectral properties of several oximes of 2-(4,5-dihydro-5-aryl-3-isoxazolyl)-1-arylethanones 6 . Unusual behaviour on its ¹H-nmr and mass spectra was observed. Single crystal X-ray diffraction was performed on compound 6d to support our structural considerations abouth the title compounds.     

Synthesis and pharmacological activity of O-(5-isoxazolyl)-L-serine

A novel isoxazole derivative, O-(5-isoxazolyl)-L-serine (OIS, 1), was synthesized by a Mitsunobu reaction of isoxazolin-5-one (4) with N-Boc-L-serine tert-butyl ester (5) and subsequent deprotection of the coupling product. Its structure was elucidated by spectroscopic analyses. The pharmacological activity of 1 was also examined with cloned glutamate receptors and transporters using a Xenopus oocyte-expressing system showing substrate activity on an excitatory amino acid carrier 1 (EAAC 1) as a glutamate transporter.     

4-(5-Methoxy-2-oxazolyl)naphthalic anhydride and products of its condensation with aromatic amines

4-(5-Methyl-2-oxoazolyl)naphthalic anhydride was synthesized by condensation of 4-chloroformylnaphthalic anhydride with aminoacetone and subsequent cyclization of the resulting amide. Luminescing methyl-substituted N-phenylnaphthalimide and 1,8-naphthoylene-1,2-benzimidazple were obtained by condensation of this product with aniline and o-phenylenediamine, respectively. The relationship between the structures of the products and their electronic absorption and luminescence spectra was investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 883–885, July, 1976.     

Synthesis and luminescence properties of anhydrides and N-phenylimides of substituted 4-(5-phenyl-2-oxazolyl)-naphthalic acids

Anhydrides and N-phenylimides of 4-(5-phenyl-2-oxazolyl)naphthalic acids with various substituents in the para position of the phenyl ring were synthesized. Electron-donor substituents, particularly the dimethylamino group, induce an appreciable long-wave shift of the absorption maxima and the luminescence due to their interaction with the carbonyl group of the peri-anhydride grouping. A large Stokesian shift and a high photoluminescence quantum yield are characteristic for the dimethylamino-substituted anhydrides.     

4-Functionally-substituted 3-heterylpyrazoles: XIX. 3-aryl-4-(5-isoxazolyl)pyrazoles

Oximes of 4-(4-pyrazolyl)-3-buten-2-onees obtained by successive reaction of 3-aryl-4-formylpyrazoles with acetone and hydroxylamine at the treatment with iodine suffered an oxidative cyclization yielding 3-aryl-4-(5-isoxazolyl)pyrazoles.     

Synthesis and glutamate-agonistic activity of (S)-2-amino-3-(2,5-dihydro-5-oxo-3-isoxazolyl)-propanoic acid derivatives.

(S)-2-Amino-3-(2,5-dihydro-5-oxo-3-isoxazolyl)propanoic acid, (3a) and its analogs (3b--h) were prepared and evaluated for glutamate receptor-agonistic and antifungal activities. Several (S)- and (R)-2-amino-3-isoxazolylpropanoic acid derivatives (3a--d) were synthesized starting with (S)- and (R)-N-tert-butoxycarbonyaspartic acid alpha-methyl esters (4, n = 1) by means of Masamune's chain extension reaction followed by isoxazolone formation with hydroxylamine and subsequent deprotection reactions. Furthermore, (S)- and (R)-N-tert-butoxycarbonylglutamic acid alpha-methyl esters (4, n = 2) were converted to (S)- and (R)-2-amino-4-isoxazolylbutyric acid derivatives (3e-h) via the same sequence of reactions.     

An experimental and theoretical study of dipole moments of N-alkyl-1,3-bis-(p-chlorophenyl)triazenes and 1-(3,4-dimethyl-5-isoxazolyl)-3-aryltriazenes

The dielectric constants, densities, and the refractive indices of dilute benzene solutions have been used to obtain the experimental dipole moments of 1,3-diphenyltriazene (1a), 1,3-diphenyl-3-methyltriazene (Ib), 1,3-bis(p-chlorophenyl)triazene (IIa), its N-alkyi derivatives (IIb-IIg), and 1-(3,4-dimethyl-5-isoxazolyl)-3-phenyltriazene (IIIb) and its N-methyl derivative (IIIc). The results show that the dipole moment of IIa is increased by an increment of about 0.77 D (average value for methyl, ethyl, n-propyl, allyl, and benzyl) on N-alkyl substitution. The increment for the n-butyl group is Δμ = 1.19 D. Some of the experimental values are compared with those from PPP and CNDO/2 calculations.     

Synthesis of ethyl (±1)-(e)-5-(4- and 5-(3-hydroxy-1-octenyl)-1-methyl-2-imidazolin-2-yl)-5-thia pentanoates

The racemic title compounds 1a,b and 2a,b were prepared from L-asparagine.     

4-(1-芳基-3-烃基-3-氧代丙胺基)-N-(5-甲基-3-异噁唑基)苯磺酰胺的 合成与抗糖尿病活性的初步研究

为寻找新型高效低毒的过氧化物酶体增殖物激活受体(PPAR)激动剂, 通过Mannich反应一步合成了13个含有磺胺甲噁唑结构单元的未见报道的β-氨基酮衍生物, 收率为39.8%～92.5%. 化合物的结构通过IR, 1H NMR, 13C NMR, ESI MS和HRMS表征. 生物活性测试结果表明, 化合物1a能够显著激活PPAR反应元件. 文中还对合成反应条件及化合物结构-活性关系进行了初步讨论.     

Synthesis and biological activity of (S)-2-amino-3-(2,5-dihydro-5-oxo-4-isoxazolyl)propanoic acid (TAN-950 A) derivatives.

(S)-2-Amino-3-(2,5-dihydro-5-oxo-4-isoxazolyl)propanoic acid (TAN-950 A (1)) is a novel amino acid antibiotic which shows a high affinity for glutamate receptors of the central nervous system. To improve the affinity for glutamate receptors, the structure-activity relationships of TAN-950 A derivatives 6a--o, 15a--o were investigated. Optically active TAN-950 A analogs 15a--h were synthesized starting with methyl (S)- and (R)-N-Boc-pyroglutamate (8) via acylation at the C-4 position followed by isoxazolone formation with hydroxylamine and subsequent deprotection reactions. The lactam 16, prepared from (RS)-aminoadipic acid, and dimethyl esters 19 of (R)- and (S)-aspartic acid were converted to (RS)-3-methyl-homo-TAN-950 A (15i) and optically active nor-TAN-950 A derivatives 15j--o, respectively, utilizing a similar sequence of reactions. Most of TAN-950 A derivatives 6a--o, 15a--o showed an affinity for glutamate receptors. The 3-alkyl derivatives 15b, d--g, especially, showed a high affinity for the quisqualate subtype-receptor and had a strong activating effect on the hippocampal neurons (glutamate agonistic activity). The (R)-enantiomer 15a of TAN-950 A had increased selectivity for the N-methyl-D-aspartate (NMDA) subtype-receptor. This selectivity was further enhanced by removal of the methylene group in the amino acid moiety of 15a. The most potent and selective NMDA agonistic activity was observed with (R)-3-methyl-nor-TAN-950 A (15m).     

Synthesis and spectral-luminescence properties of 4,4′-di(2-oxazolyl)-stilbenes and 4,4′-di(2-oxazolyl)tolans

A new method is proposed for the synthesis of 4,4-di(2-oxazolyl)stilbenes and 4,4-di(2-oxazolyl) tolans by condensation of oxazolyl-substituted benzyl bromides or benzal dibromides under the influence of strong bases (KOH, potassium tertbutoxide) in dipolar aprotic solvents [dimethylformamide (DMF) and dimethyl sulfoxide (DMSO)]. The synthesized compounds luminesce intensely over the spectral range 386–492 nm.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 463–467, April, 1981.