An efficient diastereoselective synthesis of spiro pyrido[2,1-b][1,3]oxazines via a novel pyridine-based three-component reaction

Efficient Synthesis of the Functionalized Spiro[indoline‐3,4′‐pyridine] via Four‐component Reaction

“…[1][2][3][4] Their potential properties have prompted many efforts toward the synthesis of spirooxindole-fused heterocycles. [10][11][12][13][14][15][16][17][18][19][20][21] Recently multicomponent reactions based on the sequential reactions of isatins [22,23] or benzofuran-2,3-diones [24,25] with Huisgen's 1,4-dipoles, which were formed in situ from the addition of azaarenes with electron-deficient alkynes have been successfully used to construct versatile spirooxindole systems. [10][11][12][13][14][15][16][17][18][19][20][21] Recently multicomponent reactions based on the sequential reactions of isatins [22,23] or benzofuran-2,3-diones [24,25] with Huisgen's 1,4-dipoles, which were formed in situ from the addition of azaarenes with electron-deficient alkynes have been successfully used to construct versatile spirooxindole systems.…”

Pyridine-based, microwave-assisted one-pot synthetic protocol for the synthesis of ethyl 3-substituted-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates

“…2), for the synthesis of a tetrahydropyrimidine/di-hydropyrimidine ring and its substituted 3rd-position analogues were associated with limitations, such as being a multistep synthesis, a long reaction time, harsh conditions and expensive reagents, thereby limiting their application in sustainable (''green'') chemistry. Thus, the drawbacks associated with the existing routes for the development of tetrahydropyrimidine/di-hydropyrimidine rings, and motivated by the success of the pyridine-based, three-component condensation reactions for other scaffolds [32][33][34][35], as well as continuous synthetic interests in heterocyclic rings [36][37][38], here, we report a novel, pyridine-based, microwave-assisted one-pot synthetic route for the synthesis of ethyl 3-substituted-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate derivatives in quantitative yields. Pyridine-based, microwave-assisted one-pot synthetic protocol… Experimental Chemistry All reagents and solvents were purchased from commercial sources and used without further purification.…”

Structural consequences of weak interactions in dispirooxindole derivatives

“…The heterocyclic spirooxindole ring system is a recurring structural element that has been identified in numerous naturally occurring substances (Williams & Cox, 2003), characterized by highly pronounced biological properties, and pharmacologically active compounds. These spiro-fused ring systems display stereochemical and structural complexities that continue to challenge the synthetic chemist and, as a consequence, a number of methods have been reported for the preparation of spirooxindole-fused heterocycles (Jadidi et al, 2009;Badillo et al, 2011;Esmaeili et al, 2011;Kiruthika et al, 2011). Isatin is one of the most commonly used reagents in the construction of spirooxindoles in many reactions, such as 1,3-dipolar cyclo- ISSN 2053ISSN -2296 # 2015 International Union of Crystallography addition, the Morita-Baylis-Hillman reaction and other condensation reactions (Hong & Wang, 2013;Shi et al, 2012).…”