Synthesen mit 1, 3-Dithietanen. XIII. Synthesen von kondensierten Heterocyclen aus substituierten 5-Thioxo-Δ3-pyrazolin-4-carbonsäureestern

Syntheses with 1, 3-Dithietanes. XIII. Syntheses of Condensed Heterocycles from 5-Thioxo-3-pyrazoline-4-carboxylates 3-Amino-2-aroyl-5-thioxo-3-pyrazoline-4-carboxylates 1d – f react with bromoacetal-dehydediethylacetale, phenacyl bromides, ethyl bromopyruvate, ethyl α-chloro-acetate or chloro-acetylacetone to give ethyl dihydropyrazolo[5,1-b]thiazolecarboxylates 2 , 4 , 5 or 7 . The derivatives of ethyl tetrahydropyrazolo [5,1-b]thiazolecarboxylates 8 or 9 are obtained by reaction of 1d – f with ethyl β-anilino-α-chloro-crotonate and oxalylchloride, respectively. The ethyl methylthiopyrazoline-carboxylate 10d and an excess of hydrazine hydrate afford pyrazolo[3,4-c]pyrazole 11 . Compounds 10 react with phenyl isocyanate to give pyrazolo[3,4-d][1,3]oxazin-6-ones 13 . The dithietanes 12 and cinnamohydrazide yield pyrazolo[1,2-a]pyrazolecarboxylates 15 .     

Beiträge zum Reaktionsverhalten von Derivaten der Imidodithiokohlensäure. II [1]. 7-Hydroxythiazolo[4,5-b]pyridone-(5)

Contributions to the Reaction Behaviour of Derivatives of Imidodithiocarbonic Acid. II. 7-Hydroxythiazolo[4,5-b]pyrid-5-ones Derivatives of cyanimidocarbonic acid 1 react with ethyl γ-bromoacetoacetate to ethyl thiazolylacetates 2 which are converted into 7-hydroxythiazolo[4,5-b]pyrid-5-ones 3 by acid or base catalyzed cyclisation. These compounds can be alkylated as well as acylated. The 7-hydroxy group is exchangeable for chlorine. Furthermore in position 6 electrophilic sulfonation can take place.     

3-Amino-thieno[2,3-b]furane und 3-Amino-thieno[3,2-b]furane

3-Amino-thieno[2,3-b]furans and 3-Amino-thieno[3,2-b]furans The O-alkylation of 2-hydroxy-thiophene-3-carbonitriles ( 1 ) with α-bromocarbonyl compounds yields the 2-alkoxy-thiophene-3-carbonitriles ( 2a–f ) among them 2-benzoylmethoxy-thiophene-3-carbonitriles ( 2a–c ) which undergo Thorpe-Ziegler-cyclization to form the 3-amino-2-benzoyl-thieno[2,3–b]furans ( 3 ) in low yields. The 2-acyl-3-amino-thieno[3,2–b]furans and ethyl 3-amino-thieno[3,2–b]furan-2-carboxylates ( 6 ) are synthesized in similar manner from 3-hydroxy-thiophene-2-carbonitriles ( 4 ) and α-halogencarbonyl compounds via 3-acylmethoxy- and 3-ethoxycarbonylmethoxy-thiophene-2-carbonitriles ( 5 ) with high yields.     

2,3-Heterokondensierte Thiophene aus substituiertem 2-Aminothiophen-3-thiol

2,3-Heterocondensed Thiophenes from Substituted 2-Aminothiophen-3-thiole Ethyl 5-amino-4-mercapto-3-methyl-thiophen-2-carboxylate ( 2 ), obtainable from the appropriate thienylthiocyanate 1 by reduction, undergoes reactions in analogy to the 2-aminobenzenthiole. Thus, with formic acid or trimethylorthoacetat the thieno [2,3-d]thiazoles 4 and 5 are formed. Aromatic aldehydes yield the thieno[2,3-d]thiazolines ( 6 ) which can be dehydrogenated by sulphur to form 9 . From carbon disulfide and 2 the thieno[2,3-d]thiazol-2-thione ( 7 ) is formed. With phenacylbromide or ethyl bromoacetate 2 can be converted into the thieno[3,2-b] thiazine derivatives 11 or 12 . Diazotation of 2 yields the thieno[2,3-d]1,2,3-thiadiazole derivative ( 14 ).     

6-甲基-2-苯基咪唑[2,1-b]并-1,3,4-噻二唑-5-N'-取代苯基亚甲基碳酰肼的设计与合成

根据已有的具有抗肿瘤活性的咪唑[2,1-b]并-1,3,4-噻二唑类化合物的结构及其构效关系,以2-氨基-5-苯基-1,3,4-噻二唑和溴代乙酰乙酸乙酯为原料设计并合成了8个6-甲基-2-苯基咪唑[2,1-b]并-1,3,4-噻二唑-5-碳酰肼的腙类衍生物.通过1HNMR、LC-MS、IR等方法对其结构进行了确证.     

3,4-二甲基-2,5-二甲酸乙酯噻吩[2,3-b]并噻吩选择性酰肼化

以乙酰丙酮和二硫化碳为原料合成出3,4-二甲基-2,5-二甲酸乙酯噻吩,它在不同溶剂中与过量水合肼反应,得到不同的产物:在乙醇中回流24 h,以66%的产率得到单酰肼化产物3,4-二甲基-噻吩[2,3-b]并噻吩-2-甲酸乙酯-5-甲酰肼;以DMF为溶剂80℃反应得到的主要产物是3,4-二甲基-2,5-噻吩[2,3-b...     

Untersuchungen an zwitterionischen s-Triazolo[4,3-b]pyridazinen

Studies on the Mesoionic s-Triazolo[4,3-b]pyridazines The heating of 4-amino-s-triazole, ethyl acetoacetates and alkylhalogenides afforded mesoionic s-triazolo[4,3-b]pyridazinones 2 . With P₄S₁₀ the O-atom in the 2 was exchanged through the S-atom. Both systems has a different distribution of the electronically density. It was established by the measurement of ¹H- and ¹³C-n.m.r.-spectra. Reactivity both systems was different by protonation, alkylation and nucleophilic addition reactions with dimethyl acetylendicarboxylate.     

Synthesis of Thiazolo(4,5-b)-quinoxalines and related compounds

The reaction of 2,3,7-trichloroquinoxaline ( 1 ) or 2,3-dichloro-7-bromoquinoxaline ( 2 ) with thiourea in DMSO gave 6,6′-dichloro- or 6,6′-dibromodiquinoxalino[2,3-b:2′:3′-e]1,4-dithiien ( 3 or 4 ). However, 1 or 2 reacts with thiourea in ethanol to give ( 3 or 4 ) beside 7-chloro- or 7-bromo-2-imino-2,3-dihydrothiazolo[4,5-b] quinoxaline ( 5 or 6 ) respectively. Interaction of 1 or 2 with acetone thiosemicarbazone gave 7-chloro- or 7-bromo-3-amino-2-imino-2,3-dihydro-thiazolo[4,5-b] quinoxaline hydrochloride ( 13 or 14 ) respectively. Cyclization of 7-chloro- or 7-bromo-3-amino-2-imino-2,3-dihydrothiazolo[4,5-b]quinoxaline ( 15 or 16 ) on treatment with aromatic acid chlorides or isothiocyanates succeeded to give 19—21 or 28 and 29 .     

Fluorinated surfactants: synthesis properties applications,by Erik Kissa. Marcel Dekker Inc., New York, 1994, pp. vii + 469, price US$165.00. ISBN 0-8247-9011-1

The photocoloration of a novel spirooxazine, 1-[β-(4-trifluoromethyl benzoyloxy)ethyl]-3,3-dimethyl-spiro[indoline-2,3′-[3H]-naphtho[2,1-b]-1,4-oxazine] (SO), doped in different polymer films and fibers was studied. The results show that photocoloration increased with increasing concentration of spirooxazine in polymer films. The photocoloration rate of spirooxazine in PMMA is faster than that in PS due to the polarity of the polymer films. A general model for the kinetics of photocoloration of spirooxazine in polymer films is proposed. The results also show that the photocoloration rate of spirooxazine in PET is faster than that in Nylon-6 due to the crystallinity of the polymer fibers.     

Amino-thieno[2,3–c]pyrazole und Amino-thieno[2,3–b]pyrrole

Amino-thieno[2,3–c]pyrazoles and Amino-thieno[2,3–b]pyrroles The synthesis of thieno[2,3–c]pyrazoles and thieno[2,3–b]pyrroles is described. From the dithioliumsalt ( 1 ) and potassium hydroxide the potassium-(2,2-dicyan-1-methylthio-ethen-1-yl)-thiolate ( 2 ) is formed. This reacts with hydrazine hydrate to form the 3-amino-5-thioxo-pyrazol-4-carbonitrile ( 3 ) S-Alkylation with α-chlorocarbonyl compounds yielding ( 6a–c ) leads via Thorpe-Ziegler-cyclization to 3,4-diamino-thieno[2,3–c]pyrazoles ( 9 ) if the position 1 is alkylated ( 8 ). Acetyl acetone yields 2-mercapto-pyrazolo[1,5–a]pyrimidine ( 5 ). After S-alkylation ( 10a–d ) are immediately cyclized to thieno [2′,3′:3,4]pyrazolo[1,5-a]pyrimidine ( 11a–d ). The ketone ( 6a ) can be cyclized to the pyrazolo [5,1–b]thiazole ( 12 ). 3 reacts with oxalyl chloride to form the 2,3-dioxo-6-thioxo-imidazo[1,2-b]pyrazole ( 13 ) of which S-phenacyl derivative ( 14 ) because the NH-proton cannot be cyclized. The 5-amino-3,4-dicyano-pyrrol-2-thiolate ( 16 ) shows the analogous behaviour. The S-alkylation is followed by cyclization, and 3,5-diamino-thieno[2,3–b]pyrroles ( 18a–b ) arise. Reaction of 5-amino-2-alkylthio-pyrrol-3,5-dicarbonitrile ( 17 ) with acetyl acetone provides pyrrolo[1,2-a]pyrimidine ( 20a–c ) which can be cyclized to form thieno[3′,2′:4,6]pyrimidines ( 21a–c ) very easily.     

Eindeutige Synthese des 4,7-Dihydro-4-oxo-1 H-pyrazolo[3,4-b]pyridins – Bemerkungen zur „(N?C)-Umlagerung”︁ von (2-Alkoxycarbonyl-vinyl-amino)pyrazolen

Unambiguous Synthesis of 4,7-Dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine — Further Comments on the “(N C)-Rearrangement” of (2-Alkoxycarbonyl-vinyl-amino)pyrazols 4,7-Dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine 1a is synthesized by decarboxylation of 1-benzyl-5-carboxy-4-hydroxy-pyrazolo[3,4-b]pyridine 4b and debenzylation of 1-benzyl-4,7-dihydro-4-oxo-pyrazolo[3,4-b]pyridine 1b with sodium in liquid ammonia. The product from 3-amino-pyrazol and methyl propiolate, formerly described as 1a , obviously is the 6-oxo isomer 2a . Use of the parameter δ¹³(CO) for the structural assignment of pyrazolo[3,4-b]pyridones is only permitted, if in the corresponding media mainly the oxo-tautomer is existing. It is again demonstrated that DMSO is often an insufficient medium. Debenzylation of 1b and similar compounds with SeO₂ is only possible, if the α-position of CO is blocked by a substituent. Otherwise diselenids of type 6 are formed. This obviously is a general reaction of cyclic lactames. The cyclisation of (2-alkoxycarbonyl-vinyl-amino)pyrazols 7 in acidic media, and with catalytical amounts of the corresponding amino-pyrazols gives 6,7-dihydro-6-oxo-pyrazolo[3,4-b]pyridines 2 via amino 4-(2-alkoxycarbonyl-vinyl)pyrazols 8 , i.e. via products of an “(N C)-rearrangement”, while by thermal cyclisation of 7 4,7-dihydro-4-oxo-pyrazolo[3,4-b]pyridines 1 are formed.     

Reactions with 5,6-Diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones and 6,7-Diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one

2-Methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-one 5 and 6,7-diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one 6 are prepared from 4,5-diphenyl-2-mercapto-imidazole 1 . Compounds 5 and 6 react with amines or hydrazines to give the 2-(4,5-diphenyl-imidazol-2-ylthio)acet(or propan) amides (hydrazides) 7a – g and the 3-(4,5-diphenyl-imidazol-2 ylthio) propanamides(hydrazides) 8a – e , respectively. The hydrazides 7a, 7b and 8a are condensed with aromatic aldehydes to the hydrazones 9a – h and 10a – d . Compound 5 couples with aryldiazonium salts to give 2-arylazo-2-methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones 11a – d .     

The synthesis of fused and pendant pyrazole heterocyclic compounds from 5-amino-3-methyl-1-phenylpyrazole and their evaluation as fluorescent brightening agents

5-Amino-3-methyl-1-phenylpyrazole ( 1 ) has been condensed with EMME ( 2 a) and EMCA ( 2 b) and the resulting ethyl 5-aminoacrylates ( 3 a–b) cyclized to pyrazolo[3,4,-b]pyridines ( 4 a–b). 3-Methyl-1-phenylpyrazol-5-yl diazonium salt ( 7 ), prepared from ( 1 ) was coupled with tobias acid ( 8 ) and 2-methoxy-6-aminoquinoxaline ( 9 ) to get the corresponding O-aminoarylazo and heterylazo dyes ( 10 ) which were oxidatively cyclized to 2-N-(3-methyl-1-N-phenylpyrazol-5-yl)-1,2,3-triazolo[4,5-a] naphthalene and [4,5-f] quinoxaline derivative ( 11 ). The spectral properties of the compounds ( 4 a–b, 5 , 6 , 11 a–b) were studied.     

Intramolekulare 1,3-dipolare Cycloadditionen von Arylaziden mit Alkinylsubstituenten

Intramolecular 1,3-Dipolar Cycloadditions of Aryl Azides with Alkynyl Substituents Reaction of substituted 4-chlorobut-2-ynes 1 with 2-acetaminophenol and 2-aminothiophenol, respectively, leads to the corresponding ethers and thioethers 3 that can be converted into the alkynyl substituted aryl azides 4 by diazotation and reaction with sodium azide. Intramolecular 1,3-dipolar cycloaddition yields 4H-[1,2,3]triazolo [5,1-c] [1,4] benzoxazines and benzothiazines 5 . In the same way 1,4-bis(2-acetaminophenoxy)but-2-yne 6 reacts to a 3-(2-azidophenoxy-methyl)-triazolobenzoxazine 9 . Its thermal decomposition gives the azomethine 11 .     

Allgemeine Synthesen und rationelle Strukturparameter isomerer Derivate von [3,4]-kondensierten Pyrazolen

General Syntheses and Rational Parameters for Structural Assignment of Isomeric Derivatives of [3,4]-fused Pyrazoles 4 isomeric 1- or 2-methyl-, and 1- or 2-benzyl-pyrazolo[3,4-b]pyridones, i.e. the 4-oxo-types 17a, b or 11a, b and the 6-oxo-types 16a, b or 10a, b , are synthesized unambiguously. Cyclisation of 1-substituted 3- or 5-(1-methyl-2-ethoxycarbonyl-vinylamino)-pyrazoles 9a, b or. 15a, b , which were synthesized from 1-substituted 3- or 5-amino-pyrazoles and ethyl acetoacetate yields 11a, b or 17a, b in downtherm, but 10a, b or 16a, b in presence of acidic catalysts. The acidic cyclisation is preceded by a new rearrangement of 9 or 15 into 1- substituted 3- 27 or 5-amino-4-(1-methyl-2-ethoxycarbonyl-vinyl)-pyrazoles 30 ; mechanism and concurring reactions are explained. Because of their higher electron densities at C-4 it is easier to cyclise derivatives of 5-amino-pyrazoles compared to 3-amino-pyrazoles. All isomeric 1- or 2-substituted 4(6)-chloro-6(4)-methyl-pyrazolo-[3,4-b]pyridines are formed with POCl₃ from the corresponding oxo-compounds. The position of a substituent at N-1 or N-2 of [3,4]-fused pyrazoles can be assigned using the significant ¹H-n.m.r.-parameter Δ = δ — − δ_HMPT (conc. HC—3). If solvent influences are considered, δ(C  O) is a useful ¹³C-n.m.r.-parameter to distinguish the 4-oxo-types ( 11a, b; 17a, b ) from the 6-oxo-types ( 10a, b; 16a, b ) of pyrazolo[3,4-b]pyridones. Further own and lit. dates conc. structural assignment (n.m.r., i.r., u.v.) are discussed critically.     

Studies on aminoazoles: Synthesis of Pyrazolo[1,5-a]-pyrimidines and their aza derivatives

The reaction of 4-arylazo-3-aminopyrazol-5-ones ( 1a – i ) with α,β-unsaturated nitriles, active methylene reagents and nitrile imines are reported. They lead to new polyfunctional derivatives of pyrazolo[1,5-a]pyrimidine ( 5a – c , 6 , 10a – i , 13a – c , 14a – c , 17a – d , 15 ), pyrazolo-[5,1-c]-1,2,4-triazine ( 22a – i ) and pyrazolo[5,1-c]-1,2,4-triazole ( 25a – c ). The structures of these products and the mechanisms of their formation are reported.     

5,6,7-Trihydro-5,7-diphenyl-thiazolo[3,2-b]-s-triazin-3 (2h)-one as a stabilizer for the double base propellant

5,6,7-Trihydro-5,7-diphenyl-thiazolo [3,2-b]-s-triazin-3(2H)-one (C₁₇H₁₅N₃OS) is used as a stabilizer for the double base propellant and gave good results with the stability tests. The samples were stored for 12 days at 100° C and were extracted by different suitable solvents. The column partition chromatography helped in separation of 5,6,7-trihydro-5,7-(2-nitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3(2H)-one; 5,6,7-trihydro- 5,7-(4-nitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3(2H)-one; 5,6,7-trihydro-5,7-(2,2′-dinitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3(2H)-one; 5,6,7-trihydro-5,7-(4,4′-dinitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3 (2H)-one with their different percentages.     

6-甲基-4-羟基-噻嗯并[2,3-b]噻喃-2-磺酰胺的合成

以2-巯基噻吩和巴豆酸为起始原料,经加成缩合制得3-(2-噻吩巯基)丁酸;在P2O5催化下环合制得6-甲基-4-氧-噻嗯并[2,3-b]噻喃;再用氯磺酸进行氯磺化、氨水氨解制得6-甲基-4-氧-噻嗯并[2,3-b]噻喃-2-磺酰胺;最后用硼氢化钠还原得到盐酸杜塞酰胺的中间体6-甲基-4-羟基-噻嗯并[2,3-b]噻喃-2-磺酰胺,合成总收率为16.0%。其化学结构经IR,1H NMR,MS得以确证。     

Zur Synthese und Abwandlung N-substituierter 2(1 H)-Pyrimidin-thione - Ein einfacher Zugang zu Pyrimidino[2,3-b]1,3,4-thiadiazoliumsalzen

Synthesis and Transformation of N-substituted 2(1 H)-Pyrimidine-thiones – A Simple Route to Pyrimidino [2,3-b]1,3,4-thiadiazolium Salts N-substituted 2(1 H)-pyrimidine-thiones 4–6 can be prepared by reaction of primary amines or unsubstituted or substituted hydrazines with 3-isothiocyanato-propene-(2)-iminium salts 2 , which are easily aviable from 3-chloro-propene-(2)-iminium salts 1 . The 2(1 H)-pyrimidine-thiones are transformed into 2-alkylmercapto-pyrimidinium salts 7 and pyrimidino[2,3-b]1,3,4-thiadiazolium salts 9 , respectively.     

咪唑并吩嗪基苯硼酸衍生物的合成与荧光特性研究

合成了2种含有1 H-咪唑[4,5-b]并吩嗪荧光团的苯硼酸探针分子。它们均有大的斯托克斯位移(分别为136nm和141nm)和荧光发射波长(>540nm)。其中化合物3b:(2-(1H-咪唑[4,5-b]并吩嗪-2-基)苯硼酸)的荧光强度小于3a:(4-(1H-咪唑[4,5-b]并吩嗪-2-基)苯硼酸),这是由于分子内的B-N间的相互作用影响了分子内电荷发生转移。研究表明设计合成的咪唑并吩嗪基苯硼酸类荧光糖探针可选择性识别不同结构的糖。