Syntheses of 1,5-benzothiazepines: Part XIX-Syntheses of 10-substituted benzopyranobenzothiazepines as prospective cardiovascular agents

1185-118

Diversity-Oriented Synthesis of Novel Benzimidazoles as Antimalarial agents via post Ugi MCR

An efficient strategy for the syntheses of highly diverse benzimidazoles in exceptional yields via post Ugi reactions has been described. In our methodology we have utilized isocyanide based Ugi-reaction followed by acid catalyzed condensation cyclization reaction under microwave irradiations. All benzimidazole derivatives showed moderate to good antimalarial activity when compared with chloroquine as reference compound. Among these compounds, three of them (8b), (8c), (8d) were found to be most potent towards antimalarial activity. The synthesized hybrids were examined for their purity with the help of thin layer chromatography. Different analytical techniques were employed for further characterization like Mass studies, NMRs (1H and 13C) and FT-IR

Green Chemistry: Synthesis of Bioactive Heterocycles

XIII, 412 p. 534 illus.online resource

Studies on novel polycyclic heterocycles: synthesis of new naphthaquinoxaline and naphthazaquinoxaline derivatives from naturally occurring quinones

427-433A facile synthesis of novel polycyclic heterocycles namely naphthaquinoxaline and naphthazaquinoxaline derivatives is carried out by the reaction of lapachol and β-lapachone, naturally occurring naphthoquinones with o-phenylene diamine and 2,3-diaminopyridine. Regioselectivity in the reaction of β-lapachone with 2,3-diaminopyridine is confirmed by single crystal X-ray diffraction of a representative compound 6,7-dihydro-8,8-dimethyl-8H-pyrano[3',2':4]-naphtha[2,1-e]pyrido[2,3-b]pyrazine; C₂₀H₁₇N₃O, crystallizes as orthorhombic in the space group Pbca with cell parameters a =9.793(3)Å, b=17.514(6)Å, c=18.334(6)Å, V=3144.5(17) ų, Z=8,1.332 mg/m³, R₁=0.3076, WR₂=0.3595

Synthesis of novel spiro[indole-pyranoimidazole] and spiro [indole-pyranopyrrole] derivatives

243-246<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "dejavu="" sans";mso-hansi-theme-font:minor-latin;mso-bidi-font-family:mangal;="" mso-bidi-theme-font:minor-bidi;color:#00000a;mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">An elegant one-step synthesis of two novel spiro ring systems viz., spiro [3H-indole-3,4'(1’H)-pyrano[2,3-d-imidazol]-2-oxo-2'-thiones-5' carbonitrile (VI) and spiro[3H-indole-3,4'(1’H) pyrano [2,3-c] pyrrole]-5' carbonitrioles (VII) in 44-59% yields is described. The spiro heterocycles were prepared by the Michael reactions of 3-dicyanomethylene-2H-indol-2-ones (III) with I-phenyl-2-thio-hydamoin (IV) and 2-pyrrolidone/N-methyl-2-pyrrolidone (V), respectively, while the intermediate (III) has been synthesized from substituted indole-2,3-diones (I) with malanonitrile (II). The synthesized compounds have been characterized on the basis of elemental analyses IR' 1H NMR 19F NMR and mass spectral studies. All the compounds have been screened in vitro for antifungal activity against <i style="mso-bidi-font-style: normal">Alternaria alternata.</span

Improved synthesis of trifluoromethyl substituted 3-spiro indolines and 3-indolyimines under microwaves irradiation

201-205<span style="font-size:11.0pt;line-height:115%; font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;mso-ascii-theme-font:minor-latin;mso-fareast-font-family: &quot;DejaVu Sans&quot;;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:Mangal; mso-bidi-theme-font:minor-bidi;color:#00000A;mso-ansi-language:EN-US; mso-fareast-language:EN-US;mso-bidi-language:AR-SA">The trifluoromethyl substituted 3' - phenyl spiro [3 H -indole-3-2' -thiazolidine]- 2,4' -(1H)-diones(VI) and 4,5-dihydro-3-phenyl spiro [2H-1,3-benzothiazine-2:3-[3H]-indole]-2',4 (1'H, 3H)-diones (VII) have been synthesized by the cyclo condensation of 3-indolylimines (III) with thioacids viz. Mercaptoacetic acid (IV a)/2-mercapto propionic acid (IV b) and O mercapto benzoic acid (V), under microwave in open borosil glass vessels using either ethanol as energy transfer medium or silica gel as mineral solid support. The former compound, (III) have been synthesized by the condensation reaction of indole-2,3- diones (I)and trifluoromethyl substituted anilines (II) under microwave irradiation. The comparison of synthetic procedure under microwave and classical thermal method indicates tremendous reduction in time, higher selectivity, yield and purity compared to traditional methods. Characterization of the products has been done on the basis of elemental analyses; IR 1HNMR and 19FNMR spectral data Representative compounds have been 'Screened in vitro for antifungal activity against Rhizoctonia solani, Fusarium oxysporum and Colletotrichum capsici.</span

Improved microwave induced syntheses and reactions of 2-aryl-3-(3-aryl-3oxo-propen-1-yl)-indoles with thiourea and hydrazine derivatives

159-162The potential of domestic microwave oven has been utilized to accelerate the reactions of 2-aryl-3-(3aryl- 3-oxo-propen-1-yl)-indoles (III) with hydrazine hydrate/phenyl hydrazine and thiourea, to obtain 2aryl- 3-[3-aryl-pyrazol-5-yl]-indoles <span style="font-size:11.0pt; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:arial;mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="">(IV) <span style="font-size:11.0pt; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">and 2-aryl-3-[4-aryl-5, 6-dihydro-2(1H)-thioxopyrimidine-6yl]- indole (V). The former indolyl chalcones (III) have been synthesized by the condensation of 2-aryl-1H- indole-3-carboxaldehyde (I) and fluorinated acetophenones (II) in the presence of sodium hydroxide in open borosil glass vessels under microwave irradiation, using ethanol as energy transfer medium. The results obtained demonstrate the versatility of the process as considerable reaction rate enhancement has been observed bringing down the reaction time from hours to seconds, along with improved yields. All synthesized compounds have been characterized on the basis of elemental analyses, IR, 1H NMR, 19F NMR and mass spectral studies.</span

Facile chemoselective synthesis of novel 6-aryl-12<i style="">H</i>-indolo[2,3-<i style="">e</i>][1,4]benzodiazocine derivatives by the reaction of 3-aroylmethylene-2<i style="">H</i>-indol-2-ones with <i style="">o</i>-phenylenediamine

1135-1139 Syntheses of 6-aryl-12H-indolo[2,3-e][1,4]benzodiazocine deri­vatives 8 have been achieved for the first time by the reaction of 3-aroylmethylene-2H-indol-2-ones 4 with o-phenylenediamine 5 While the analogous reaction of 4 with ethylene diamine 9 resulted in exclusive formation of Schiff base derivatives viz. 1,3-dihydro-3-[2- (2-aminoethylimino)-2-aryl-ethylidene]indol-2-ones 12. The structures are assigned with the help of analytical and 1H, 13C NMR, DEPT, IR and mass spectral studies.</smarttagtype

A facile catalyst and solvent-free synthesis of spiro thia heterocycles on grinding

An efficient and mild method for the synthesis of spiro [1,3- oxathiolan/oxathianes] in the solid state reaction at room temperature has been described. This method is a good option to obtain the title compounds in quantitative yields in a simple and inexpensive way. Applying this methodology, different thia heterocycles were synthesized

Facile one-pot synthesis of new annulated hexacyclic ring system indeno-pyrano-furo-indoles and spiro indenopyran-indoles under microwave irradiation

1001-1005An efficient and clean procedure for the synthesis of a new hexacyclic system indeno-pyrano-furo-indoles 8 and spiroindoles incorporating pentacyclic ring system spiro[indenopyran-indoles] 6 using inorganic solid support under microwave irradiation is described