Pyrylium[2,3-b]indole salts

2-Ketoindoline and 1-methyl-2-ketoindoline condense with hydroxymethylene ketones in the presence of hydrogen chloride to give pyrylium[2,3-b]indole chlorides, which can be converted to 5-(3-oxindolyl)-²-pyrazolines by reaction with phenylhydrazine and to 5-(3-oxindolyl)-²-isoxazolines by reaction with hydroxylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1030–1032, August, 1972.     

Thieno [2,3 -b] pyridines and thieno [ 3,2 -b] pyridines by the method of gould-jacobs

Bis(2-, and 3-thienylammonium) hexachlorostannates were condensed with ethoxymethylene derivatives of active methylene compounds in pyridine. The resulting condensation products IVa-IVc and Va-Vc on heating under reflux in Dowtherm or diphenyl ether provided various 4-hydroxythieno[2,3-b] pyridines (Ia-Ic) and 7-hydroxythieno[3,2-b]pyridines (IIa-IIc). The compound Ic on further transformations gave yet other derivatives If-Ik.     

Synthesis of New Thieno[2,3-b:5,4-c']dipyridines

We describe the formation of thieno[2,3-b:5,4-c]dipyridines from 5,6-dihydropyridine-2(1H)-thiones. The two-step reaction mechanism was revealed by isolation of an intermediate. The oxo and thioxo groups of the obtained tricyclic compounds were hydrogenated selectively. The structures of all new compounds were elucidated by NMR experiments.     

噻吩并[2,3-b]吡啶类化合物的合成及生物活性

用邻氨基噻吩腈与不同结构的二羰基化合物反应,合成了新的多取代噻吩并吡啶类衍生物4-氨基-5-取代羰基噻吩并[2,3-b]吡啶-6-酮。用元素分析、红外光谱、核磁共振氢谱和质谱等测试技术对所合成化合物的结构进行了表征。初步生物活性测试表明,该类化合物有较好的杀菌活性和一定的除草活性。     

Synthesis and Properties of New Fluorine-Containing Thieno[2,3-b]pyridine Derivatives

Russian Journal of General Chemistry - Cyanothioacetamide reacted with 1,1,5,5-tetrafluoroacetylacetone to give 4,6-bis(difluoromethyl)-2-thioxo-1,2-dihydropyridine-3-carbonitrile, and alkylation...     

Fused indoles. 1. Synthesis of the 1,9-dihydrothiazino[3,4-b] indole ring system

The title compounds were prepared by treating 2-chloroindole-3-carboxaldehydes and 3-acetyl-2-chloroindole with N-methylmethanesulfonamide and cyclizing the resulting intermediates with sodium hydride. Spectral data of the products are also discussed. J. Chem. Soc., 14, 1117 (1977)     

噻吩并[2,3-b]吡啶化合物的合成及应用

噻吩并[2;3-b]吡啶;生物活性;医药;农药;合成     

Highly Efficient Synthesis of Thieno[2,3‐b]indole Derivatives

Thieno[2,3‐b]indole derivatives were efficiently prepared via the reaction of 1,3‐dihydro‐2H‐indole‐2‐thiones with α‐bromo‐substituted ketones or aldehydes and in the presence of Et₃N (Scheme 2 and Table). The reaction took place under very mild conditions and in short times with good to excellent yields.     

Synthesis of New Thieno[2,3-b]pyridine Derivatives Based on Fused Thiophenes

Russian Journal of Organic Chemistry - Conditions for the Gewald synthesis of 2-amino-5,5-dimethyl-4,7-dihydro-5H-thieno[2,3-c]pyrans from 2,2-dimethyltetrahydropyran-4-ones have been optimized,...     

Chemistry of Thienopyridines. XXIV. Two Transformations of Thieno[ 2,3-b] pyridine 7-Oxide

Refluxing thieno[2,3-b ]pyridine 7-oxide ( 1 ) with aeetic anhydride plus subsequent hydrolysis produced a mixture of thieno[2,3-b]pyrid-6(7H)one ( 2 ) (13%) and 5-hydroxythieno[2,3-b]-pyridine ( 4 ) (4%). Refluxing 1 with phosphorus oxychloride yielded a mixture of 4- and 6-chloro-thieno[2,3-b]pyridines, ( 5 ) (54%) and ( 6 ) (31%), respectively. Compound 6 was also obtained directly from 2 (31%). A mechanistic rationalization for the isomerization of 1 to form 2 and 4 is presented. Marked differences in the mass spectral fragmentations of these three isomeric compounds are noted.     

Synthesis of 4H-furo[3,2-b]indole derivatives A new heterocyclic ring system

4H-Furo[3,2-b]indole (III) was prepared from deoxygenation of 2-(2-nitrophenyl)furan (II) with triethyl phosphite and thermolysis of 2-(2-azidophenyl)furan (VI). 4H- or 4-alkylfuro [3,2-b]indole-2-carboxaldehydes (VIII, IXa-c) were obtained by Vilsmeier formylation of the corresponding furo[3,2-b]indoles (III, VIIa-c). 4H-Furo[3,2-b]indole-2-carboxaldehyde (VIII) was submitted to the Cannizzaro, Wittig and reduction reactions. The Shiff's bases were obtained by the reaction of 4-ethylfuro[3,2-b]indole-2-carboxaldehyde (IXb) with amines. J. Heterocyclic Chem., 14, 975 (1977)     

Synthesis and Application of 2-Arylazo-3-Cyano Thieno [2,3-b]Naphthoquinones

The paper describes the synthesis of 2-amino-3-cyanothieno[2,3-b]naphthoquinone and its utilisation to prepare range of azo disperse dyes. These novel arylazo dyes were studied with respect to their color and constitution relationship. Application of these dyes on polyester fibres and their fastness properties were stated. These dyes were characterised by PMR, IR and visible absorption spectra.     

Disruption of Crystal Packing in Thieno[2,3-b]pyridines Improves Anti-Proliferative Activity

3-Amino-2-arylcarboxamido-thieno[2,3-b]pyridines have been shown to have anti-proliferative activity, but are also known to have poor solubility. This has been previously proposed to be due to their extensive planarity, which allows for intermolecular stacking and crystal packing. We herein report the synthesis of fifteen novel thieno[2,3-b]pyridines that have incorporated bulky, but easily cleavable, ester and carbonate functional groups in an effort to decrease crystal packing. The addition of these ‘prodrug-like’ moieties into the thieno[2,3-b]pyridine resulted in compounds with increased activity against HCT-116 colon cancer cells and the triple-negative breast cancer cell line MDA-MB-231.     

The Thieno[2,3-c]pyridine Reissert Compound

Thieno[2,3-c]pyridine has been converted to 6-benzoyl- and 6-carbethoxy-7-cyano-6,7-dihydrothieno[2,3-c]-pyridine. Alkylation, condensation, Michael addition, and cyclo addition reactions of these Reissert type compounds have been carried out.     

Benzo[f]isoindole analogs II. Thieno[3,4-b]quinoxaline

The transient existence of thieno[3,4-b]quinoxaline ( 2d ) as a product of dehydration of 1,3-dihydrothieno[3,4-b]quinoxaline 2-oxide ( 5 ) was demonstrated by trapping experiments with N-phenylmaleimide and dimethyl acetylenedicarboxylate. Attempts to isolate 2d from reaction mixtures arising from dehydration of 5 and from dehydrogenation of 1,3-dihydro-thieno[3,4-b]quinoxaline ( 8 ) were unsuccessful.     

Synthesis and Reaction of Some Indenopyridine and Thieno[2,3-b]Indeno[2,1-e]Pyridine Derivatives

Synthesis of indenopyridine-2-thione derivatives 6a-e via reaction of compound 1 with thioamides 2a-e in good yields. Several thieno[2,3-b]indeno[2,1-e]pyridine 9a-e have been synthesized. Some of them was used as a key intermediate in synthesis of 10-12. On the other hand, compound 1 reacted with various reagents to yield 16, 19, 21-24.     

Selenium heterocycles. XXXIII. Synthesis of thieno[3,4-b]furan,seleno[3,4-b]furan,thieno[3,4-b]indole and seleno[3,4-b]indole. four novel heterocycles

Starting from the readily available 2-methyl-3-benzoylfuran, 1-phenylthieno[3,4-b]furan and 1-phenyl-seleno[3,4-b]furan were prepared. Also, starting from phenyl 3-methylindol-2-yl ketone and aryl 2-methyl-indole-3-yl ketones a series of substituted thieno[3,4-b]indoles and substituted seleno[3,4-b]indoles were prepared.     

Synthesis and Cyclizations of N-(Thieno[2,3-b]pyridin-3-yl)cyanoacetamides

Russian Journal of General Chemistry - 3-Aminothieno[2,3-b]pyridine-2-carboxylic acid esters readily reacted with 3,5-dimethyl-1-(cyanoacetyl)-1H-pyrazole to give previously unknown...