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991.
Aniruddha Das 《合成通讯》2017,47(23):2254-2267
Investigation into Sonogashira reaction on 5-iodo-1-(phenyl/p-halophenyl)imidazole-4-carbonitrile compounds had been developed by introducing an iodo atom at the C-5 position of the imidazole ring of 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carbonitrile compounds. Specifically, 5-iodo-1-(4-iodophenyl)imidazole-4-carbonitrile compound had shown double Sonogashira coupling reactions with two differently substituted iodine along with the formation of two other compounds where an unusual coupling product with self-aggregation property was obtained. In other cases, monocoupling had been observed together with another compound where iodine atom present at C5 position of imidazole was replaced by hydrogen atom. 相似文献
992.
An efficient one-step method to prepare aryl-substituted carbazoles via tandem double or triple CC bond formations by multiple Suzuki couplings and CN bond formation by Cadogan cyclization has been developed. The developed method employs commercially available or easily preparable polybromonitrobenzenes and arylboronic acids as starting materials, tolerates various functional groups, and provides good yields. 相似文献
993.
A modular approach to 5-acylated naphtho[2,1-b]benzofurans was developed where Sonogashira cross-coupling and intramolecular alkyne carbonyl metathesis were sequentially employed to build the aromatic benzene C ring of naphtho[2,1-b]benzofuran with an acyl group at the C5 position. 相似文献
994.
Francisco Lara-Ochoa Leticia C. Sandoval-Minero Georgina Espinosa-Pérez 《Tetrahedron letters》2017,58(1):43-45
A new strategy for a large scale synthesis is developed and evaluated by the improvement of the current synthesis for fenleuton, a drug with important applications in leukotriene-mediated inflammatory diseases that acts through inhibition of the 5-lipoxygenase enzyme. 相似文献
995.
Cuiling Wang Jiaxu Yan Mo Du Joseph A. Burlison Chi Li Yanni Sun Danqing Zhao Jianli Liu 《Tetrahedron》2017,73(19):2780-2785
One step synthesis of the natural product indirubin by reductive coupling of isatin with KBH4 is described and a possible mechanism for the reaction is proposed. Eleven indirubin derivatives were obtained easily from the corresponding substituted isatin. 相似文献
996.
(E)-2-(6-((E)-2-carboxyvinyl)-2,3-dihydroxyphenyl)-3-(3,4-dihydroxyphenyl) acrylic acid, designated SMND-309, was synthesized starting from 2-hydroxy-3-methoxybenzaldehyde in 12 steps and with an overall yield of 44%. The synthetic key features were the conversion of aryl aldehyde into aryl acetic acid for one-carbon extended, the Perkin condensation, and the Heck coupling for construction of α,β-unsaturated ester. 相似文献
997.
A practical copper-catalyzed I-substitutions of alkyl-2-iodobenzoates with alkynes have been developed using Cu powder as a catalyst under solvent, cocatalyst, and base-free conditions. This reaction system is new, facile, efficient, and economical that gives Sonogashira coupling products in excellent yields (up to 97%). The coupled products (A–J) were characterized by CHNS, 1H NMR, and 13C NMR and are found soluble in ethyl acetate and dichloromethane. In addition, simulation studies of A–J were performed with aspulvinone dimethylallyltransferase enzyme and observe good binding affinity. The reported compounds may act as anti-cizmatics, anti-fobic in future and also have the inhibition of aspulvinone dimethylallyltransferase properties to control Alzheimer’s, Schizophrenia, etc. diseases. 相似文献
998.
Jiyuan Ge Jian Jiang Chenhuan Yuan Chaozhi Zhang Minghua Liu 《Tetrahedron letters》2017,58(12):1142-1145
Water soluble phosphine ligand triphenylphosphine-3,3′,3″-trisulfonic acid trisodium salt (TPPTS) was used as the stabilizer as well as the activator to the palladium nanoparticles, which showed a high catalytic performance for aqueous phase Suzuki-Miyaura coupling reaction at room temperature. 相似文献
999.
Shankaraiah Malthum Naveen Polkam Tejeswara Rao Allaka Kalyani Chepuri Jaya Shree Anireddy 《Tetrahedron letters》2017,58(44):4166-4168
We present a convenient route for the synthesis of C6-amino-C5′-N-cyclopropyl carboxamido-C2-alkynylated purine nucleoside analogues 11a–g via Sonogashira coupling reaction. The nine step synthesis is easy to perform, employing commercially available reagents. Compound 9 is used as key intermediate for the synthesis of analogues 11a–g. Synthetic intermediates and final products are appropriately characterized by IR, 1H NMR, 13C NMR and Mass. The modified nucleoside analogues 11a–g is evaluated for in vitro anticancer activity against MDA-MB-231 and Caco-2 cell lines. Screening data reveals that compounds 11b and 11e displayed potent IC50 value of 7.9, 6.8 µg/mL respectively against MDA-MB-231 and of 7.5, 8.3 µg/mL respectively against Caco-2 than the standard drug doxorubicin, thus establishing the potential anti-cancer properties of these newer derivatives. 相似文献
1000.
Sanjay Jadhav Gajanan Rashinkar Rajashri Salunkhe Arjun Kumbhar 《Tetrahedron letters》2017,58(33):3201-3204
A simple, efficient and metal-free route for the synthesis of dissymmetric ketones through Suzuki type cross-coupling reaction has been established. This strategy signifies an attractive, cost-effective and operationally convenient tool for the synthesis of a wide range of dissymmetric ketones. Although conventional routes for the synthesis of ketones have been widely used, the potential challenge with these methods is functional group tolerance. The reported metal-free method represents a reaction with moderate functional group tolerance. The procedure is operationally convenient and shows broad substrate scope with good to excellent product yields. 相似文献