Highly stereoselective construction of spiro[cyclopropane-1,4′-pyrazolin-5′-one]with 4-arylidene-3-methyl-1-phenyl-pyrazolin-5-one and arsonium ylide

A highly stereoselective synthesis of exo-spiro[cyclopropane-1,4′-pyrazolin-5′-one] from 4-arylidene-3-methyl-1-phenyl-pyrazolin-5-one and arsonium bromide in the presence of base has been achieved. The triphenylarsine-catalyzed cyclopropanation of 4-arylidene-3-methyl-1-phenyl-pyrazolin-5-one with bromide in the presence of NaHCO₃ has also been studied. Both exo and endo isomers were formed in this reaction. The structures of the products were characterized by IR, MS, ¹H NMR, elemental analysis, and X-ray diffraction analysis.     

Synthesis of new aryl substituted furan-2(5H)-ones using the Suzuki-Miyaura reaction

A series of novel 5-arylidenefuran-2(5H)-ones and 5-arylidene-4-arylfuran-2(5H)-ones were synthesized via the Suzuki-Miyaura reactions of fimbrolide derivatives 5-(bromomethylene)furan-2(5H)-one and 4-bromo-5-(bromomethylene)furan-2(5H)-one, respectively. A regioselective Suzuki-Miyaura reaction on 4-bromo-5-(bromomethylene)furan-2(5H)-one allowed the synthesis of unsymmetrically substituted 5-arylidene-4-arylfuran-2(5H)-ones. The crystal structure of the intermediate 5-arylidene-4-bromofuran-2(5H)-one revealed interesting Br?O halogen bonding.     

1H, 13C and 15N NMR spectral characterization of twenty-seven 1,2-diaryl-(4E)-arylidene-2-imidazolin-5-ones

1H, 13C and 15N NMR chemical shifts and couplings (n)J(H,C) in DMSO-d(6) at 30 degrees C have been determined for 1,2-diaryl-(4E)-arylidene-2-imidazolin-5-one derivatives 1-27. Their chemical shift assignments are based on PFG DQF 1H,1H COSY, PFG 1H,13C HMQC as well as PFG 1H,13C and 1H,15N HMBC experiments. For compounds 1-10 including aryl fluorine substituent(s) also the couplings (n)J(F,C) (n = 1 - 4) are reported.     

微波辅助合成5-亚甲基-2,3-二苯基-4-噻唑酮类衍生物

本文报道了一种通过微波辅助合成5-亚甲基-2,3-二苯基-4-噻唑酮类衍生物的新型方法。在以K2CO3 为碱、H2O 为溶剂、四丁基溴化铵（TBAB）为催化剂的条件下,2,3-二苯基-4-噻唑酮与取代醛在微波辅助下发生Knoevenagel 反应,生成5-亚甲基-2,3-二苯基-4-噻唑酮类衍生物,产率最高可达85%。     

Synthesis and structural determination of novel 5-arylidene-3-N(2-alkyloxyaryl)-2-thioxothiazolidin-4-ones

As part of our project devoted to the synthesis of heterocycles including thiazole rings, some new 5-arylidene-2-thioxo-3-N-arylthiazolidin-4-ones were synthesized by Knoevenagel condensation. An interesting feature of these compounds is that their chirality is induced by that of their 3-N-(2-alkyloxyaryl)-2-thioxothiazolidin-4-one precursors, which in turn is due to the presence of a C2 axis of chirality. These new compounds were characterized by spectroscopic methods (IR, 1H-NMR, 13C-NMR). The structure of compound (Z)-(2g) was further determined by X-ray diffraction.     

Synthesis of 3,4-dihydro-2H-pyrans by hetero-Diels-Alder reactions of functionalized alpha,beta-unsaturated carbonyl compounds with N-vinyl-2-oxazolidinone

Cycloadditions of 3-aryl-2-benzoyl-2-propenenitriles and 3-phenylsulfonyl-3-buten-2-one to N-vinyl-2-oxazolidinone proceed regio- and diastereoselectively yielding cis and trans diastereoisomers of 4-aryl-3,4-dihydro-2-(2-oxo-3-oxazolidinyl)-2H-pyrans in 37-65% yield. Cycloadducts cis- were the major products. Reaction of 5-arylidene-1,3-dimethylbarbituric acids with dienophile afforded mixtures of 2H-pyrano[2,3-d]pyrimidine-2,4(3H)-diones trans and products resulted from an elimination of 2-oxazolidinone, in 50-52% yield. To confirm the experimental results, semiempirical AM1 and PM3 calculations of frontier orbital energies have been performed.     

Efficient and facile synthesis of 5-arylindeno[2′,1′:5,6]pyrido[2,3-d] pyrimidine-2,4(3H)-dione and 7-arylbenzo[h]pyrimido[4,5-b]quinoline-8,10(5H,9H)-dione under mild conditions

An efficient and facile method for the synthesis of 5-arylindeno[2′,1′:5,6]pyrido[2,3-d] pyrimidine-2,4(3H)-dione and 7-arylbenzo[h]pyrimido[4,5-b]quinoline-8,10(5H,9H)-dione derivatives from the reactions of 2-arylidene-2,3-dihydroinden-1-one (or 2-arylidene-3,4- dihydronaphthalen-1(2H)-one) and 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione under mild conditions was described. This is a simple, efficient, and very rapid synthetic method, which is believed to provide a useful process for the synthesis of these fused heterocyclic compounds. The products were confirmed by infrared, ¹H NMR, ¹³C NMR, and high-resolution mass spectrometry.     

Facile synthesis of 4-arylidene-5-imidazolinones as synthetic analogs of fluorescent protein chromophore

A facile and effective synthesis for a wide variety of 4-arylidene-5-imidazolinone derivatives was developed. 4-Arylidene-5-oxazolinones were prepared by Erlenmeyer azlactone synthesis from N-acylglycines and arylaldehydes. The ring-opening reactions of the 4-arylidene-5-oxazolinones with primary amines afforded 2-acylamino-3-arylacrylamides in excellent yields. A new dehydrative cyclization of the 2-acylamino-3-arylacrylamides in pyridine under reflux furnished the corresponding 4-arylidene-5-imidazolinones in good yields.     

An efficient construction of C?N bond under catalyst-free and room temperature conditions

An efficient and facile process for the construction of C N bond from 1,6-conjugate addition reaction of 4-arylidene-2,6-di-tert-butylcyclohexa-2,5-dien-1-one (or substituted 3-[3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene]indolin-2-one) and substituted 1,2,3,4-tetrahydroisoquinoline (or substituted indoline) at room temperature was reported. The advantages of this reaction were catalyst-free, mild condition, broad substrate scope, and environmentally benign process.     

A convenient approach to heterocyclic building blocks: synthesis of novel ring systems containing a [5,6]Pyrano[2,3-c]pyrazol-4(1H)-one moiety

Starting from commercially available educts, a straightforward synthetic route to new heterocyclic building blocks is exemplified with the one- or two-step synthesis of tri-, tetra-, or pentacyclic ring systems. Representatives of the following novel ring systems are prepared from 3-methyl-1-phenyl-2-pyrazolin-5-one and the corresponding o-halo-arenecarbonyl chloride using calcium hydroxide in refluxing 1,4-dioxane: pyrimidino[4',5':5,6]pyrano[2,3-c]pyrazol-4(1H)-one, thieno[3',2':5,6]pyrano[2,3c]pyrazol- 4-(1H)-one, thieno[3',4':5,6]pyrano[2,3-c]pyrazol-4(1H)-one, thieno[3',2':4',5']thieno[2',3':5,6]-pyrano[2,3-c]pyrazol-4(1H)-one, [1,3]dioxolo[5',6'][1]benzothieno[2',3':5,6]pyrano-[2,3-c]- pyrazol-4(1H)-one, pyridazino[4',3':5,6]pyrano[2,3-c]pyrazol-4(1H)-one and pyrazolo-[4',3':5',6']pyrido[3',4':5,6]pyrano[2,3-c]pyrazol-4(1H)-one. While the latter two ring systems are directly obtained due to a spontaneous intramolecular substitution reaction, in the other reactions uncyclised 4-aroylpyrazol-5-ols are produced, which are cyclised into the target heterocycles in a subsequent synthetic step (i.e. treatment with NaH in DMF). Detailed NMR spectroscopic investigations ((1)H-, (13)C-, (15)N-) with the obtained compounds were undertaken to unambiguously prove the new structures.     

Heterophase N-aminomethylation of 5-arylidenepseudothiohydantoins by arylamines and aqueous formaldehyde in aromatic solvents: Effect of substituents in the heterocyclic substrate and the aryl amine on the efficiency of the process

We have obtained a series of 3-aryl-7-arylidene-3,4-dihydro-2H-[1,3]thiazolo[3,2-a][1,3,5]triazin-6(7H)-ones by means of heterophase aminomethylation of 2-amino-5-arylidene-1,3-thiazol-4(5H)-ones with aqueous formaldehyde and aromatic amines in benzene or toluene. We explain the effect of substituents in the heterocyclic substrate and the aryl amine on the efficiency of the process within a detailed scheme for one of the possible aminomethylation reaction routes. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1095–1104, July, 2006.     

Five new peltogynoids from underground parts of Iris bungei: a Mongolian medicinal plant

Five new peltogynoids, irisoids A-E (1-5), have been isolated from the underground parts of Iris bungei. The structures of the new compounds were established on the basis of spectroscopic methods and were found to be 1,8,10-trihydroxy-9-methoxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (1), 1,8-dihydroxy-9,10-dimethoxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (2), 1,10-dihydroxy-8,9-dimethoxy-[1]benzopyrano-13,2-c][2]-benzopyran-7(5H)-one (3), 1,8-dihydroxy-9,10-methylenedioxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (4), and 1,8,11-trihydroxy-9,10-methylenedioxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (5). The structure of irisoid B (2) was established unambiguously by X-ray diffraction study.     

Chemical transformations of mackinazolinone and its derivatives

The thioanalog of mackinazolinone (2,3,4,10-tetrahydro-1 H-pyrido[2,1-b]quinazolin-10-one) was synthesized for the first time by reacting it with P₂S₅. The thioanalog was reacted with aromatic aldehydes and Vilsmeier- Haack reagent (DMF + POCl₃) to produce 4-arylidene- and -hydroxymethylidenemackinazolinthiones, respectively. The reactions of 4-hydroxymethylidenemackinazolinone with isomeric aminophenols and aminobenzoic acids and of hydroxymethylidenemackinazolinthione with thionylchloride were studied. Subsequent reaction of the obtained 4-chloromethylidene derivative with sodium hydroselenide was synthesized a new Se-containing derivative of mackinazolinone. It was shown that 4-formylmackinazolinthione existed in the enol form whereas 4-formylmackinazolinone existed as the enaminoaldehyde tautomer.     

在三乙基苄基氯化铵相转移催化下水相中(E)-3-亚苄基-2,3-二氢吲哚-2-酮衍生物的合成

以芳醛和2,3-二氢吲哚为原料, 以水为溶剂, 在室温以三乙基苄基氯化铵为催化剂合成了一系列的(E)-3-亚苄基-2,3-二氢吲哚-2-酮衍生物. 该方法具有反应条件温和、立体选择性好、产率高(72%～96%)和环境友好等优点. 产物的结构通过熔点, IR, ¹H NMR和元素分析表征.     

2-取代-3-芳基-4-噻唑啉(硫)酮衍生物的合成、晶体结构和生物活性

从2-取代-3-芳基-4-噻唑啉酮(4a～4e和5)合成了三个系列新型噻唑啉酮衍生物, 即5-芳基亚甲基-4-噻唑啉酮(6a～6j), 4-噻唑硫酮(7a～7e和8)和4-氰基亚胺基噻唑烷(11a～11e和12). 中间体4a～4e和5由醛、胺和巯基乙酸缩合得到. 所有化合物的结构均经元素分析和¹H NMR确证, 并且采用X射线单晶衍射分析方法测定了化合物4b的结构. 初步生物活性试验结果表明, 部分标题化合物具有一定的杀菌活性和促进黄瓜子叶生根活性.     

(5R,6R)-6-苯基-5-(苯磺酰基乙酰基)二环[2.2.1]-2-庚烯的合成及结构表征

报道了一种制备4-苯基-1-苯磺酰基-3-丁烯-2-酮的新合成方法. 4-苯基-3-丁烯-2-酮与溴化试剂Ph₃P^＋CH₂CH₂- COOHBr 作用, 得到1-溴-4-苯基-3-丁烯-2-酮, 不经分离直接与苯亚磺酸钠发生亲核取代反应, 得到4-苯基-1-苯磺酰基-3-丁烯-2-酮. 将此反应产物作为亲双烯体与环戊二烯在手性钛金属催化剂催化下进行不对称Diels-Alder反应, 得到了＞99% ee 的环加成产物(5R,6R)-6-苯基-5-(苯磺酰基乙酰基)二环[2.2.1]-2-庚烯. 用X衍射法对产物的晶体结构进行了测定, 讨论了反应机理, 通过元素分析, NMR, MS对产物的结构进行了表征.     

Condensation reactions at the methylene group of 1-(4-nitrophenyl)-pyrrolin-2-one and 1-(4-nitrophenyl)-pyrrolin-2-onium perchlorate

The interaction has been investigated of 1-(4-nitrophenyl)pyrrolin-2-one with aromatic aldehydes in acetic anhydride in the presence of catalytic amounts of pyridine. 1-(4-Nitrophenyl)pyrrolinium perchlorate has been synthesized and was put into a condensation reaction with aromatic aldehydes. As a result 5-arylidene-1-(4-nitrophenyl)pyrrolin-2-onium perchlorates were obtained. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1015–1021, July, 2006.     

Synthesis and Antimicrobial Activities of Some 6-Methyl-3-Thioxo-2,3-Dihydro-1,2,4-Triazine Derivatives

Abstract

4-Arylidene-imidazole derivatives (4a,b) were readily prepared by reacting 4-am- ino-6-methyl-3–thioxo-2,3–dihydro[1,2,4]triazin-5(4H)-one (1) with 4-arylidene-2-phenyl- 4H-oxazol-5-one (2). Reaction of 1 with some aromatic aldehydes in presence of triethylphosphite exclusively afforded the corresponding aminophosphonates 5a-c. Reaction of 1 with 3-phenyl-1H-quinazoline-2,4-dione (6a) and/or 3-phenyl-2-thioxo-2,3-dihydro- 1H-quinazolin-4-one (6b) gave 2-(6-methyl-5-oxo-3-thioxo-2,5-dihydro-3H-[1,2,4]triazin-4-ylimino)-3-phenyl-2,3-dihydro-1H-quinazolin-4-one (7). Moreover, on treating 1 with 2-phenylbenzo[d][1,3]thiazine-4-thione (8), 6-methyl-4-(2-phenyl-4-thioxo-4H-quinazolin-3-yl)-3-thioxo-3,4-dihydro-2H-[1,2,4]triazine-5-one (9) was obtained in 65% yield. Reaction of 1 with 4-sulfonylaminoacetic acid derivatives (10a,b) afforded the corresponding sulfonamides (11a,b), respectively. Acid hydrolysis of 11a afforded 7-aminomethyl-3-methyl[1,3,4]thiadiazole[2,3-c][1,2,4]triazin-4-one (12). 4-Amino-6-methyl-3-(morpholine-4-ylsulfanyl)-4H-[1,2,4]triazin-5-one (14) was prepared by reacting compound 1 with morpholine in presence of KI/I₂, while 3,3′-bis(4-amino-6-methyl-5-oxo-triazinyl)disulfide (16) was obtained by oxidation of 1 with lead tetraacetate. The antimicrobial activity of the products was evaluated against Gram-positive and Gram-negative bacteria as well as the fungus Candida albicans.

[Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text, figures, and tables.]     

Solid state reactions of nitrogenous heterocyclic compounds(Ⅰ)——Solid state reactions of 3-methyl-l-phenyl-5-pyrazolone with carbonyl compounds

The solid state reaction of 3-methyl-1-phenyl-5-pyrazolone (MPP) with aromatic aldehydes and ke-tones benzil derivatives and imides,and the solid state Michael addition reaction of MPP with 4-arylidene-3-methyl-1-phenyl-5-pyrnzolone 2 were investigated.Some new solid state reactions between the reactants were found,from which a series of new compounds were obtained The structures of the products were identified by IR,1H NMR,MS,elemental analyses and also by X-ray crystal analysis,and the reaction mechanism of MPP with aromatic aldehydes and ketones was proposed     

Efficient Syntheses of New 2,2′-Disubstituted-2,3-dihydrofuran Derivatives and Natural Polyketide Analogues

Efficient syntheses of new 2,2′-disubstituted-2,3-dihydrofuran(5H)-4-one,spiro{benzofuran-2,2′-bicyclo[2.2.1]heptan}-4(5H)-one derivatives, and natural polyketide analogues have been achieved via the oxidative [3 + 2] cycloaddition of 1,3-dicarbonyl compounds with monoterpenes myrcene, camphene, and natural phenyl propenes, namely anethole and safrole respectively. Interestingly, the reaction of isoprene and myrcene with 1,3-dicarbonyl compounds yielded 2,2-disubstituted tetrahydrobenzofuran-4(5H)-one derivatives at room temperature. Thus, several substituted 2,3-dihydrofuran derivatives (3a–3h) with potential biological activity have been synthesized.