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1.
L. A. Ignatova P. L. Ovechkin A. E. Gekhman B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1976,12(12):1333-1336
The relative basicities of 4,4,6-trimethyl-2-arylamino-5,6-dihydro-4H-1,3-thiazines and 4,4,6-trimethyl-2-arylamino-5, 6-dihydro-4H-1,3-oxazines, which are capable of amine-imine tautomerism, and of model compounds with fixed amine and imine structures were determined by potentiometric titration in methanol. Good correlation of the pK
a
values with the Hammett constants in the investigated reaction series was found. The inapplicability of the use of the pK
a
values of model compounds for the determination of the tautomeric equilibrium constants in the case of some N-heterocyclic amines of nonaromatic character with an aryl substituent attached to the exocyclic nitrogen atom of the amidine fragment of the molecule is demonstrated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1621–1624, December, 1976. 相似文献
2.
Peresleni E. M. Engoyan A. P. Zotova T. D. Sheinker Yu. N. Ignatova L. A. Unkovskii B. V. 《Chemistry of Heterocyclic Compounds》1977,13(3):278-284
It is shown by means of IR, PMR, and UV spectra that 4,4,6-trimethyl-2-arylamino-5, 6-dihydro-4H-1,3-thlazines and 4,4,6-trimethyl-2-arylamino-5,6-dihydro-4H-1,3-oxazines in the crystalline state and in solution exist primarily in the amino form. It was found that ionization to give cations proceeds more readily in the case of 1,3-oxazines than in the case of 1,3-thiazines. In addition, a decrease in the ability to undergo intermolecular association and a decrease in the energy barrier to rotation about the N-heteroring bond are observed for 1,3-oxazines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 346–352, March, 1977. 相似文献
3.
L. A. Ignatova A. E. Gekhman P. L. Ovechkin B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1974,10(3):307-309
3,4,4,6-Tetramethyl-2-aryliminotetrahydro-1,3-oxazines were synthesized by intramolecular cyclization of N-aryl-N′-methyl-N′-(2-methyl-4-hydroxy-2-pentyl)-S-methylisothioureas. 4,4,6-Trimethyl-2-(N-methyl-N-arylamino)-5,6-dihydro-4H-1,3-oxazines were obtained by methylation of 4,4,6-trimethyl-2-arylamino-5,6-dihydro-4H-1,3-oxazines. 相似文献
4.
L. A. Ignatova P. L. Ovechkin M. Z. Branzburg A. E. Gekhman B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1972,8(8):939-942
4,4,6-Trimethyl-2-alkyl(aryl)amino-5,6-dihydro-4H-1,3-oxazines were synthesized via two methods: amination of 4,4,6-trimetiiyl-2-methylthio-5,6-dihydro-4H-1,3-oxazine and cyclization of N-aryl-N-(2-methyl-4-hydroxy-2-amyl)-S-methylisothiourea.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1037–1040, August, 1972. 相似文献
5.
5,6-Dihydro-4H-1,3-oxazine hydrobromides have been synthesized by the nucleophilic autocyclo-O-alkylation of N-(3-bromopropyl)amides under neutral conditions in chloroform. It is found that electron-donating amide α-substituents influence the autocyclization efficiency. 相似文献
6.
S. S. Mochalov D. V. Kosynkin I. D. Yudin V. N. Atanov Yu. S. Shabarov N. S. Zefirov 《Chemistry of Heterocyclic Compounds》1994,30(5):527-532
1,4-Diazepin-2-ones have been prepared from 1,4-benzodioxine for the first time.M. V. Lomonosov State University, Moscow 119899. Translated from Khimiya Geterotsiklcheskikh Soedinenii, No. 5, pp. 601–607, May, 1994. Original article submitted April 10, 1994. 相似文献
7.
利用多组分1,3偶极环加成反应方法,合成了一种新的螺环结构1'-甲基-3'-吡啶甲酰基-4'-(2-噻吩基)螺[吲哚啉-3,2'-吡咯啉]-2-酮化合物,并对该化合物进行了红外光谱、核磁共振谱及X-射线单晶衍射表征.单晶衍射结果表明:该晶体属于三斜晶系,空间群为P-1,晶体参数为a=0.899 9(1)nm,b=0.914 4(1)nm,c=1.271 1(2)nm,α=92.852(1)°,β=107.305(2)°,γ=101.580(1)°.在分子晶体结构中,吡咯啉环采用了信封式构象,通过螺碳原子与吲哚啉环相连,形成刚性螺环结构,2个环接近垂直构型,其二面角为84.15(2)°. 相似文献
8.
9.
M. V. Loseva B. M. Krasovitskii B. M. Bolotin 《Chemistry of Heterocyclic Compounds》1970,6(12):1491-1494
Chloro- and bromo-substituted 2-(2-tosylaminophenyl)-4H-1,3-benzoxaz-4-ones and 2-(2-tosylaminophenyl)-4H-naphtho[2,3-d]-1,3-oxaz-4-ones, their absorption spectra at room temperature, and their luminescence spectra at 77 deg K are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1597–1601, December, 1970. 相似文献
10.
V. I. Avramenko P. A. Sharbatyan Z. F. Solomko L. V. Pribega 《Chemistry of Heterocyclic Compounds》1979,15(6):691-694
Mono- and dibromo derivatives were obtained in the bromination of 4-(p-methoxyphenyl)-2,3-dihydro-1H-1, 5-benzodiazepin-2-one in media with different acidities with N-bromosuccinimide in carbon tetrachloride. The UV, PMR, and mass spectra of the compounds obtained are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 842–846, June, 1979. 相似文献
11.
A. A. Gaponov Z. F. Solomko N. Ya. Bozhanova E. I. Pantyukh 《Chemistry of Heterocyclic Compounds》1989,25(7):836-836
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, p. 997, July, 1989. 相似文献
12.
A practical synthesis of optically pure 1-[(3R,4R)-1-cyclooctylmethyl-3-ethoxycarbonyl-4-piperidinyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one (J-113397) was developed that avoids the use of chiral columns. 相似文献
13.
14.
1 INTRODUCTION Phthalimide and its derivatives are synthetic mate- rials, which are widely used as important chemical intermediates of biosensors[1] and many drugs such as Citalopran[2], luminal[3], Beta-Lactam[4] and the No. three generation quinolones[5], and they have been identified as active groups of some drugs and chemical luminescence reagents[6, 7]. Tert-butyl 4- [(E)-4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1- butenyl] benzoate is an intermediate of a new type of insulin sen… 相似文献
15.
A. Siewiński J. Dmochowska-Gładysz T. Kołek A. Zabża K. Derdziński 《Tetrahedron》1979,35(11):1409-1414
The microbiological reduction of (±)-l-(2',2',3'-trimethylcyclopent-3'-en-l'-yl)-propan-2-one (4) and (±)-1-(2',2',3'-trimethylcyclopent-3'-en-l'-yl)-butan-2-one (5) by Rhodotorula mucilaginosa was investigated. Both enantiomers of 4 are reduced stereospecifically to corresponding alcohols; (+)-(2S, l'R)-(2',2',3'-trimethylcyclopent-3'-en-l'-yl)-propan-2-ol (6) and (-)-(2S,l'S)-(2',2',3'-trimethylcyclopent-3'-en-l'-yl)-propan-2-ol (7). p ]The substrate selectivity in the reduction of 5 was observed: R enantiomer of 5 yields stereospecifically (+)-(2S,1'R)-(2',2',3'-trimethylcyclopent-3'-en-l'-yl)-butan-2-ol (8) while S(-)5 remains unchanged. 相似文献
16.
Kulakov I. V. Shulgau Z. T. Turdybekov K. M. Turdybekov D. M. Sadyrbekov D. T. 《Russian Journal of General Chemistry》2015,85(2):467-471
Russian Journal of General Chemistry - New 5,6-dihydro-1,3-thiazin-4-one derivatives have been synthesized by one-pot reaction of morpholin-4-amine and adamantan-1-amine with methacryloyl... 相似文献
17.
The synthesis and characterization of the first examples of two tellurium compounds based on 2-phenyl-5,6-dihydro-4H-1,3-oxazine substrate are described. Intramolecular Te?N interaction in [2-(2-phenyl-5,6-dihydro-4H-1,3-oxazinyl)] tellurenyl chloride is established by single X-ray crystallography. 相似文献
18.
《合成化学》2015,(10)
以2,2'-双二苯基磷基-1,1'-联萘[(S)-1]为原料,与H2O2经氧化反应制得(S)-2,2'-双二苯基磷氧基-1,1'-联萘[(S)-2];(S)-2经酸性树脂催化硝化制得(S)-5,5'-二硝基-2,2'-双二苯基磷氧基-1,1'-联萘[(S)-3)];(S)-3经Pd/C催化硝基氢化还原制得(S)-5,5'-二氨基-2,2'-双二苯基磷氧基-1,1'-联萘[(S)-4];(S)-4经HSi Cl3/PPh3还原制得(S)-5,5'-二氨基-2,2'-双二苯基膦基-1,1'-联萘,总产率65.6%,其结构经1H NMR,31P NMR和IR确证。 相似文献
19.
Mauricio G. Constantino Paulo M. Donate Nicola Petragnani 《Tetrahedron letters》1982,23(10):1051-1054
A short synthesis of racemic natural product (1) from the known compound (7) is described. A model study, using cyclochexanone as starting material, is also reported. 相似文献
20.
An efficient approach for the preparation of functionalized 4-(1,3-dioxo-2,3-dihydro-1H-2-indenyl) substituted 1-benzylpyrrole-3-carboxylates is described. This four-component reaction between ninhydrin, 1-phenyl-2-(1,1,1-triphenyl-λ5-phosphanylidene)-1-ethanone, primary amines and alkyl acetoacetate proceeds in MeOH under reflux condition in good to excellent yields. 相似文献