Transformations of sym-octahydroxanthene-1,8-diones and 1,8-dioxo-sym-octahydroxanthylium salts in recyclization under the influence of amines

The chemical behavior of 9-R-sym-octahydroxanthene-1,8-diones and salts based on them in recyclization reactions under the influence of amines was studied. The effect of the basicity of the amines on the direction of recyclization was established. A method is proposed for the single-stage synthesis of sym-octahydroacridine-1.8-dione oximes based on 1,8-dioxo-sym-octahydroxanthenes. Conditions were worked out for the oxidation of sym-octahydroxanthene-1,8-diones and N-R-decahydroacridinediones to the corresponding salts. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 32–38, January, 2006.     

Nanorod vanadatesulfuric acid (VSA NRs)-catalyzed green synthesis of hexahydroacridine-1,8-diones in solvent-free conditions

Nanorod vanadatesulfuric acid (VSA NRs), as a novel, recyclable and eco-benign catalyst, was used for an efficient synthesis of hexahydroacridine-1,8-diones using 1,3-cyclohexanedione derivatives, aldehydes and ammonium acetate or aniline under solvent-free conditions. VSA was prepared by the reaction of high-purity chlorosulfonic acid and sodium metavanadate. The present method offers some advantages over conventional ones, such as simple procedure and work-up, short reaction times, high yields, stability and reusability of the catalyst and simple purification of the products. Also, some greenness aspects of this method were investigated and compared with data from previous reports.     

微波促进下9-芳基氢化吖啶-1,8-二酮的合成研究

本文研究了微波促进下芳香醛、5,5-二甲基-1,3-环己二酮与碳酸氢铵的三组分无溶剂缩合反应,并通过该反应合成了一系列9-芳基氢化吖啶-1,8-二酮类化合物.这一合成方法具有操作简便、反应条件温和、产率高、对环境友好等特点.     

Regioselective synthesis of 3,4,6,7-tetrahydro-3,3-dimethyl-9-phenyl-2H-xanthene-1,8(5H,9H)-diones through ascorbic acid catalyzed three-component domino reaction

An efficient, three-component domino reaction of dimedone 1, aromatic aldehydes (2a–o), and 1,3-cyclohexanedione 1a in the regio-selective synthesis of 3,3-dimethyl-9-phenyl-2H-xanthene-1,8(5H,9H)-diones (3a–o) is reported. The desired product, 3 is efficiently promoted by ascorbic acid as an organo catalyst.     

An efficient one-pot solvent-free synthesis and photophysical properties of 9-aryl/alkyl-octahydroxanthene-1,8-diones

A facile and efficient protocol for the synthesis of 9-aryl/alkyl-3,3,6,6-tetramethyl-1,2,3,4,5,6,7,8-octahydroxanthene-1,8-diones has been developed by one-pot reaction of dimedone with aldehydes in the presence of InCl₃ or P₂O₅ under solvent-free conditions. The optical behaviors of the xanthenediones have been investigated by UV-vis and fluorescence spectroscopy. The present approach offers the advantages of simple methodology, clean and mild reaction, high atom-economy, short reaction time, low environmental impact, wide substrate scope, high yield, and excellent purity.     

Water mediated catalyst-free efficient domino synthesis of 9-(quinolin-2(1H)-one)-xanthene-1,8(5H,9H)-diones using parallel synthesizer

A facile and efficient method for the preparation of 3,4,6,7-tetrahydro-9-(1,2-dihydro-2-oxoquinolin-3-yl)-2H-xanthene-1,8(5H,9H)-diones from substituted 2-chloro-3-formylquinoline and 1,3-cyclohexanedione or dimedone in water at 90 °C using parallel synthesizer is reported. The present methodology offers a tandem-cascade methodology, high yield, and operational simplicity.     

Mass Spectrometric Fragmentation of 1-（Benzyloxycarbonyl）amino-2-alkyl/cycloalkyl Thioacetates： a Thioester Pyrolysis-type Rearrangement under Electron Impact Ionization

Many four- and six-membered ring rearrangements have been observed under mass spectrometric ionization conditions to date1-7. 1-(Benzyloxycarbonyl)amino-2-alkyl/ cycloalkyl thioacetates are key intermediates for the synthesis of 1-substituted and cyclic t…     

3,3,6,6-四甲基-9-(3,4-亚甲二氧基苯基)-1,8-二氧代-2,3,4,5,6,7-六氢夹氧蒽的合成和晶体结构

标题化合物C24H26O5是由胡椒醛、达咪酮在微波辐射下反应而得,反应在5分钟内完成。结构通过单晶 X-射线衍射法测定,其晶体属三斜晶系,空间群P, a = 7.1338(1), b = 10.4406 (3), c = 14.3323(4) , a = 82.56(1), b = 89.37(1), g = 78.94(1), V = 1038.73(4) 3, Mr = 394.45, Z = 2, Dc = 1.261 g/cm3, l = 0.71073 ? m(MoKa) = 0.088 mm-1, F(000) = 420, R = 0.0648, wR = 0.1588。在分子结构中吡喃环为船式构象,2个的环己酮环为信封式结构。     

3,3,6,6-四甲基-9-对氯苯基-1,8-二氧代-2,3,4,5,6,7-六氢氧杂蒽的合成和晶体结构

标题化合物C2 3H2 5O3Cl是由对氯苯甲醛与 5,5 二甲基 1 ,3环己二酮在乙二醇中反应而得。结构通过单晶X 射线衍射法测定 ,其晶体属于单斜晶系 ,空间群P2 1 /n ,a =6.0 4 8(1 ) ,b =1 9.543(3) ,c =1 7.42 0 (3) ,β =97.2 9(1 )° ,V =2 0 4 2 .2 (6) 3,Mr=384.90 ,Dc=1 2 52 g/cm3,Z =4,μ(MoKα) =2 .0 6cm- 1 ,F(0 0 0 ) =81 6。晶体结构用直接法解出 ,经用全矩阵最小二乘法对原子参数进行修正 ,最终的偏离因子为R =0 .0 39,Rw=0 .0 4 7。X 射线衍射分析表明 :平面 1 (C(8) -C(9) -C(1 9) )与平面 2 (C(1 0 ) -C(1 1 ) -C(1 2 ) )之间的两面角为1 6.2 4° ;平面 1与平面 3(C(7) -C(8) -C(9) )之间的两面角为 1 77.37° ;平面 1与平面 4(C(1 )-C(5) -C(6) )之间的两面角为 98.2 1°;平面 2与平面 3之间的两面角为 1 61 .1 2° ;平面 2与平面 4之间的两面角为 81 .98°;平面 3与平面 4之间的两面角为 79.1 5°     

Peculiarities of formation of decahydroacridine-1,8-diones on the basis of 1,3-dioxocyclohexane compounds in various media

The conditions for the formation of N-substituted decahydroacridine-1,8-diones from -R-methylenebiscyclohexane-1,3-diones and 5,5-dimethyl-3-(N-methylamino)-2-cyclohexen-1-one in ethanol, isopropanol, and DMSO have been studied. Methods have been developed for preparation of 1,8-dioxo-10-methyldecahydroacridines which contain furyl and 5-nitrofuryl substituents at the 9 position.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 475–481, April, 2000.     

Prototropy,Intramolecular Interactions,Electron Delocalization,and Physicochemical Properties of 1,8-dihydroxy-9-anthrone—DFT-D3 Study of Substituent Effects

1,8-dihydroxy-9-anthrone are tricyclic compounds with a ketone group in the middle ring and two hydroxyl groups substituted in the side-aromatic rings what results in formation of two intramolecular hydrogen bonds in which the oxygen atom from the ketone group is the proton acceptor. 1,8-dihydroxy-9-anthrones in which intramolecular proton transfer between C10 and CO in the middle ring occurs, can exist in a tautomeric keto-enol equilibrium. For anthralin, the most important representative of this group, this equilibrium has been studied previously, but it has not been studied for its derivatives. Substituents in the middle ring change the geometry of 1,8-dihydroxy-9-anthrones so they are also expected to affect the keto-enol equilibrium. It is also important to study the effect of intramolecular hydrogen bonds on the structure of both tautomeric forms. It was found that the nature of the substituent in the middle ring could affect the antioxidant properties of the investigated compound.     

反相液相色谱质谱法分离鉴定3,4,6,7,9,10-6H-3,3,6,6-四甲基-9-对硝基苯基吖啶-1,8二酮

应用反相高效液相色谱法，分离和鉴定3，4，6，7，9，10－6H－3，3，6，6－四甲基－9－对硝基苯基吖啶－1，8－二酮（化合物Ⅰ），分离系统包括Zorbax SB C18及苯基柱，紫外检测器检测波长为285nm，等比和线性梯度淋洗，液相色谱－质谱联用和光导二极和列检测系统被用来鉴定主要化合物及其它杂质，此方法可达到分离效果好，灵敏度高。     

Some transformations of N-(2,3-epoxypropyl)-1,8-naphthosultam

A method of synthesis has been developed for N-(2,3-epoxypropyl)-1,8-naphthosultam and some transformations of this compound were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 236–242, February, 2000.     

取代螺环戊烷的电子轰击和化学电离正,负离子质谱

本文报道了苯取代螺环戊烷衍生物的电子轰击(EI)正离子和化学电离正、负离子(PNCI)质谱。通过亚稳离子测定,研究了该类化合物的裂解机理。在卤代螺环戊烷的EI质谱中,分子离子峰都很弱,甚至不出现M 离子。其特征离子为[M-X]~ 、[M-2X] 和[M-X-HX]~ 。CI正离子谱有较强的[M H]~ 、[M-2X]~ 和[M-x]~ ,CI负离子谱的特征离子为[M X]~-,它们在多数情况下为基峰离子,另外还出现HX_2~-或X~-离子。     

Synthesis of 5-arylidene-3-(4′-bromobenzyl)thiazolidine-2,4-diones

Potential antihistamines 5-arylidene-3-(4′-bromobenzyl)thiazolidine-2,4-diones were synthesized using 5-arylidenethiazolidine-2,4-dione potassium salt and 4-bromobenzyl bromide in dry acetone. The log P values are given for all the synthesized compounds. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1854–1858, December, 2005.     

The Reaction of 5-Aryl(hetaryl)-2-aroylmethylthio-1,3,4-oxadiazoles with Aryldiazonium Tetrafluoroborates

5-Aryl(hetaryl)-2-aroylmethylthio-1,3,4-oxadiazoles behave as CH acids and readily react with aryldiazonium tetrafluoroborates at the active methylene group to give azo coupling products. The spectroscopic properties of the compounds synthesized have been studied.     

Intermolecular Phenolic Hydroxy Methylation Occurring between Chiral N,N''''-Bis(2-hydroxyphenyl)-2,2-dimethyl-1,3-dioxolane-4,5-dicarbamide and Co-crystallized Methanol under Electron Impact Ionization Conditions

Introduction Chiral C2-symmetric bisamides are an important and useful type of ligands, which have been widely used in asymmetric catalysis.1-7 They were used successfully in asymmetric molybdenum (0)-catalyzed allylic substitu-tion,2-5 palladium-catalyzed alkylation,1,6 and Lewis acid-catalyzed asymmetric nucleophilic ring opening of epoxides,7 etc. In addition, bisamides are useful ligands for coordination chemistry8 and are used as building blocks9 for the synthesis of dissymmetrical tetra…     

Synthesis of 3-alkyloxazolidin-2,4-diones using 2-chloroacetamides, carbon dioxide and 1,8-diazabicyclo[5.4.0]undecene (DBU)

Diazabicyclo[5.4.0]undecene (DBU) reacts with carbon dioxide and N-subsititued-2-chloroacetoamides in a very simple one-step procedure, to give the corresponding 3-substituted oxazolidin-2,4-diones in excellent yields.     

Mass Spectral Fragmentation of (S,S)-N,N′-Bis [1-(hydroxymethyl)alkyl]anthracene/Naphthalene-1,8-dicarboxamides under Electron Impact Ionization Conditions

The mass spectrometric fragmentation of(S,S)-N,N′-bis[1-(hydroxymethyl)alkyl]anthracene/naphthalene-1,8-dicarboxamides was investigated with the aid of mass-analyzed ion kinetic energy spectrometry and the elemental compositions of important fragment ions were determined by accurate mass measurement under electron impact ionization conditions. All the compounds could eliminate formaldehyde. The [M-CH2O] ions could also eliminate imine, aziridine, aziridinone,2-amonoalkan-1-ol, water, and other fragments. Several cyclizations were observed under electron impact ionization.     

1-(N-苄氧羰基-氨基)-烷基膦酸单酯的正离子电喷雾电离多级质谱特征碎裂

作为一类重要的酶抑制剂,瞵酸酯可被认为是酶的过渡态类似物。由于它不易被水解因而常被用作酶的抑制剂,或者作为具有酰胺或酯酶活性的催化抗体。鉴于其特殊的生物活性,目前已经报道了很多此类物质的合成方法。袁承业院士的研究小组曾经对苄氧羰基保护的芳基氨基膦酸的二乙酯或二异丁酯进行过细致的EI-MS分析,发现其倾向于发生P-Ca键断裂,以及产生C(O)-NH键断裂的碎片。我们也曾报道了苄氧羰基保护的芳基氨基膦酸的二甲酯和二乙酯的ESI-MSn,其碎裂方式与EI-MS中不同,不仅发生