Synthesis and anticonvulsant activity of 3-alkyl-3,4-dihydro-2(1H)-quinazolinones

Previously we reported the potent anticonvulsant activity of 3-dimethylamino-3,4-dihydro-2(1H)-quinazolinone. In this report, a series of 3-alkyl-3,4-dihydro-2(1H)-quinazolinones was synthesized in three steps from isatoic anhydrides or an anthranilic acid. Structure/activity investigations revealed optimal activity for the 3-isopropyl and 3-cyciohexyl analogs. These compounds were effective against seizures induced by maximal electroshock.     

1-Alkyl-4-aryl-3,4-dihydro-2(1H)-quinazolinones and thiones. Synthesis and 1H-NMR spectra

A series of 1-alkyl-4-aryl-3,4-dihydro-2(1H)-quinazolinones and thiones were prepared by a modification of the Pictet-Spengler reaction that involves treatment of an N-alkyl-N-arylurea or thiourea with an aryl aldehyde in the presence of methanesulfonic acid. The ¹H-nmr spectra of several of these compounds gave rise to unusual OCH₂O and isopropyl signals.     

FT-IR and NMR investigation of 2-(1-cyclohexenyl)ethylamine: a combined experimental and theoretical study

FT-IR and (1)H, (13)C, DEPT, HETCOR, COSY, and NOESY NMR spectra of 2-(1-cyclohexenyl)ethylamine (CyHEA) have been reported for the first time. The vibrational frequencies and (1)H, (13)C NMR chemical shifts of CyHEA (C(8)H(15)N) have been calculated by means of the Hartree-Fock (HF), Becke-Lee-Yang-Parr (BLYP) and Becke-3-Lee-Yang-Parr (B3LYP) density functional methods with 6-31 G(d) and 6-31 G(d,p) basis sets, respectively. The comparison between the experimental and the theoretical results indicates that density functional B3LYP method is superior to the scaled HF and BLYP approach for vibrational frequencies and predicting NMR properties.     

8,9-Methylenedioxy-3,4-dihydro-1,4,5-benzotriazocin-2(1H)-ones

The title compounds are obtained directly on reaction of 6-chloroacetamidopiperonal with substituted phenylhydrazines. Piperonal was used as starting material.     

Investigation on 2,3′-biquinolyl series. 21. Reactions of 1′-alkyl-4′-aryl-1′,4′-dihydro-2,3t′-biquinolyls and 1′-alkyl-2′-aryl-1′,2′-dihydro-2,3′-biquinolyls with sulfur

A method has been developed for the synthesis of 2′-and 4′-aryl-2,3′-biquinolyls based on the reaction of 1′-alkyl-2′-aryl-1′,2′-dihydro-2,3′-biquinolyls and 1′-alkyl-4′-aryl-1′,4′-dihydro-2,3′-biquinolyls with sulfur in DMF. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1517–1519, October, 2006.     

3-Amino-4-aryl-1(2H)-isoquinolones

3-Amino-4-aryl-1(2H)-isoquinolones have been synthesized by treating 2-halobenzamides with arylacetonitriles. The angle of rotation of the 4-phenyl grop has been determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 378–380, March, 1991.     

Novel one-pot, three-component synthesis of new 2-alkyl-5-aryl-(1H)-pyrrole-4-ol in water

New 2-alkyl-5-aryl-(1H)-pyrrole-4-ol derivatives were synthesized via three-component reaction of beta-dicarbonyl compounds with arylglyoxals in the presence of ammonium acetate in water at room temperature.     

Synthesis and some properties of 4-alkyl-5-cyano-6-mercapto-3,4-dihydropyridin-2(1H)-ones

Condensation of propionic (or acetic) aldehyde, cyanothioacetamide, Meldrum's acid, andN-methylmorpholine occursvia the intermediate formation of the corresponding Michael adducts and yields 4-alkyl-5-cyano-6-mercapto-3,4-dihydropyridin-2(1H)-ones. The oxidation of the reaction products with DMSO and their alkylation were studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2016–2019, November, 1997.     

The preparation of 3,4-dihydro-1-benzoxepin-5(2H)-ones

Several methods for the preparation of 3,4-dihydro-1-benzoxepin-5(2H)-ones are described. In addition to the desired ketones, a variety of novel by-products have been isolated.     

A facile synthesis of 2,3-dihydro-2-aryl-4（1H）-quinazolinones catalyzed by scandium（Ⅲ） triflate

2,3-Dihydro-2-aryl-4(1H)-quinazolinones were prepared in good yields via condensation of o-aminobenzamide with aldehydes promoted by a catalytic amount of Sc(OTf)_3 under mild conditions.     

Synthesis and Crystal Structure of 4-（4-Bromophenyl）- 3,4-dihydro-6-methyl quinolin-2（1H）-one

The title compound (C16H14BrNO) has been synthesized by the reaction of p-tolylamine, Meldrum’s acid and 4-bromo-benzaldehyde, and its structure was characterized by IR, 1H NMR and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 7.6850(11), b = 8.3004(11), c = 21.301(3) , β = 95.110(2)°, V = 1353.4(3) 3, Mr = 316.19, Z = 4, Dc = 1.552 g/cm3, μ(MoKα) = 3.028 mm-1, F(000) = 640, the final R = 0.0345 and wR = 0.0768. X-ray analysis reveals that the atoms of C(1), C(2), C(3), C(4), C(5) and N(1) form a six-membered ring of boat conformation.