Pteropodine and isopteropodine positively modulate the function of rat muscarinic M(1) and 5-HT(2) receptors expressed in Xenopus oocyte

Rapid and efficient ultrasound-assisted method for the combinatorial synthesis of spiro[indoline-3,4'-pyrano[2,3-c]pyrazole] derivatives

An efficient one-pot synthesis of spiro[indoline-3,4'-pyrano[2,3-c]pyrazole] derivatives by four-component reaction of hydrazine, β-keto ester, isatin, and malononitrile or ethyl cyanoacetate catalyzed by piperidine under ultrasound irradiation is described. This synthesis was confirmed to follow the group-assistant-purification chemistry (GAP) chemistry process, which can avoid traditional chromatography and recrystallization purifications.

Sonochemical multi-component synthesis of spirooxindoles

New and efficient multi-component methods have been developed for the synthesis of spirooxindoles in the presence of a catalytic amount of p-TSA as an inexpensive and available catalyst in EtOH under ultrasound irradiation. The method is simple, starts from readily accessible commercial starting materials, and provides biologically interesting products in good yields and short reaction times.

An Efficient, One-Pot Synthesis of Spiro[Dihydropyridine-Oxindole] Compounds under Catalyst-Free Conditions

An efficient one-pot synthesis of the biologically important spiro[dihydropyridine-oxindole] scaffolds from isatins, 2-naphthylamine and 1,3-dicarbonyl compounds in poly (ethylene glycol) 400/H2O under catalyst-free conditions is described. The reaction is free of catalysts and toxic solvents, operates under neutral conditions and allows for ease of product isolation, making it more environmentally friendly and suitable for large-scale operations.

Simple three-component method for the synthesis of spiroindeno[1,2-b]pyrido[2,3-d]pyrimidine-5,3'-indolines

An efficient, simple, and catalyst-free synthesis of spiroindeno[1,2-b]pyrido[2,3-d]pyrimidine-5,3'-indolines and spiroacenaphthylene-1,4'-indeno-1,5'-pyrido[2,3-d]pyrimidines by the three-component reaction of 1,3-indandione, amino uracils and isatins or acenaphthylene-1,2-dione in refluxing ethanol is reported.

Novel, one-pot, three-component route to indol-3-yl substituted spirooxindole derivatives

A simple and efficient approach to the synthesis of a novel series of polysubstituted 6'-(1H-indol-3-yl)-1',7'-dihydrospiro[indoline-3,4'-pyrazolo[3,4-b]pyridine]-2-one derivatives in high yields was developed from a one-pot, three-component reaction of 3-cyanoacetyl indoles, isatins, and 1H-pyrazol-5-amines in H(2)O/HOAc.

Efficient one-pot synthesis of novel spirooxindole derivatives via three-component reaction in aqueous medium

A novel and efficient one-pot synthesis of spiro[indoline-3,4'-pyrazolo[3,4-b]quinoline]dione, spiro[furo[3,4-e]pyrazolo[3,4-b]pyridine-4,3'-indoline]dione, and spiro[indeno[2,1-e]pyrazolo[3,4-b]pyridine-4,3'-indoline]dione derivatives via three-component reaction of isatin, 5-amino-3-methylpyrazole, and 1,3-dicarbonyl compounds in aqueous medium is described. The advantages of this method include high efficiency, mild reaction conditions, convenient operation, and environmentally benign conditions.

Efficient one-pot synthesis of spirooxindole derivatives catalyzed by L-proline in aqueous medium

An efficient one-pot synthesis of spirooxindole derivatives by three-component reaction of isatins, malononitrile (cyanoacetic ester) and 1,3-dicarbonyl compounds in water in the presence of l-proline is reported. This new protocol has the advantages of environmental friendliness, higher yields, shorter reaction times, low cost, and convenient operation.

Ultrasound promoted greener synthesis of spiro[indole-3,5'-[1,3]oxathiolanes in water

An aqueous mediated novel synthesis of substituted 2'amino-4'benzoyl-2'-methyl spiro[indole 3,5'-[1,3]oxathiolane]-2(1H)-ones (2a-f) was carried out from the reaction of spiro [indole-3,2'-oxiranes] (1a-f) with thioacetamide in the presence of LiBr as catalyst. The reaction was carried out under both microwaves and sonication and results were also compared with conventional method. In general, improvement in rate and yields observed when reaction was carried out under sonication as compared to microwave irradiation and conventional method.

Ultrasound-assisted one-pot, three-component synthesis of spiro[indoline-3,4'-pyrazolo[3,4-b]pyridine]-2,6'(1'H)-diones in water

A simple, facile, efficient and three-component procedure for the synthesis of spiro[indoline-3,4'-pyrazolo[3,4-b]pyridine]-2,6'(1'H)-diones by the reaction of 4-hydroxycumarin, isatins and 1H-pyrazol-5-amines in water under ultrasonic irradiation is reported. The advantages of this method are the use of an inexpensive and readily available catalyst, easy work-up, good yields, and the use of water as a solvent that is considered to be relatively environmentally benign.

Stereoselective synthesis of spirocyclic oxindoles via Prins cyclizations

The synthesis of spirocyclic oxindole pyran and oxepene frameworks using highly stereoselective Prins cyclizations of homoallylic and bis-homoallylic alcohols and isatin ketals is described.

A facile synthesis and antimycobacterial evaluation of novel spiro-pyrido-pyrrolizines and pyrrolidines

An efficient synthesis of 1-methyl-3-[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones was achieved by the reaction of 1-methyl-4-piperidone and aromatic aldehydes in the presence of pyrrolidine under solvent-free microwave irradiation. These dipolarophiles upon cycloaddition with nitrile oxide and azomethine ylides afford stereoselectively novel spiro-isoxazolines, pyrrolizines and pyrrolidines respectively in excellent yields. The spiro compounds were screened for their in vitro activity against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant M. tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC(2)) using agar dilution method. Among the synthesized compounds, 1-methyl-4-(2,4-dichlorophenyl)pyrrolo(spiro[2.3'']oxindole)spiro[3.3']-1'-methylpiperidin-4'-one was found to be the most active with a minimum inhibitory concentration (MIC) of 1.76 and 0.88 microM against MTB and MDR-TB respectively.

A Green Efficient Synthesis of spiro[indoline-3,4′(1H‘)-pyrano [2,3-c]pyrazol]-2-one derivatives

A highly efficient and green method has been described for the synthesis of spiropyranopyrazole-oxindole in water. The reaction was carried out at ambient temperature and the products were obtained in excellent isolated yields. The structure of the product (4e) was confirmed by X-ray diffraction analysis.