56893-13-1Relevant academic research and scientific papers
Enantiopure substituted pyridines as promising antimalarial drug candidates
Agnamey, Patrice,Bentzinger, Guillaume,Dassonville-Klimpt, Alexandra,Guillon, Jean,Marchivie, Mathieu,Pair, Etienne,Sonnet, Pascal,Mullié, Catherine
supporting information, (2020/03/13)
We describe the enantioselective synthesis and biological evaluation of 4-(2-amino-1-hydroxyethyl)pyridines (4 AHPs) as new antimalarial drug candidates. In particular, two routes to obtain the key-intermediate 4-vinyl-pyridine were studied. These routes are based on a Kr?hnke-type cyclization or on metal-catalyzed reactions. The Kr?hnke-type cyclization route is faster but only efficient at low scale since this pathway involves a Wittig reaction that requires severe temperature-control. Consequently, we designed a second route based on metal-catalyzed reactions. This way is longer but the 4-vinyl-pyridine can be obtained on a 5 g scale at least. Finally, a regioselective SN2 ring-opening of enantiopure epoxides by alkyl primary amines allowed the synthesis of eight 4-AHPs with global yields up to 41%. These compounds show strong in vitro antimalarial activity against P. falciparum strains and are more active that chloroquine and mefloquine. These results demonstrate that 4-AHPs are promising antimalarial drug candidates.
A Ba/Pd Catalytic System Enables Dehydrative Cross-Coupling and Excellent E-Selective Wittig Reactions
Xie, Peizhong,Fu, Weishan,Cai, Xinying,Sun, Zuolian,Wu, Ying,Li, Shuangshuang,Gao, Cuiqing,Yang, Xiaobo,Loh, Teck-Peng
supporting information, p. 7055 - 7059 (2019/09/12)
A Ba/Pd cooperative catalysis system was developed to enable the dehydrative cross-coupling of allylic alcohols with P-ylides to occur directly and promote a subsequent Wittig reaction in one pot. A variety of multisubstituted 1,4-dienes were isolated in good to excellent yields with broad P-ylides (stabilized by both ester and ketone carbonyl groups) and aldehyde (aliphatic and aromatic) substrates with excellent E selectivity.
Catalytic Cyclooligomerization of Enones with Three Methylene Equivalents
Farley, Conner M.,Zhou, You-Yun,Banka, Nishit,Uyeda, Christopher
supporting information, p. 12710 - 12714 (2018/10/09)
Cyclic structures are highly represented in organic molecules, motivating a wealth of catalytic methods targeting their synthesis. Among the various ring-forming processes, cyclooligomerization reactions possess several attractive features but require addressing a unique challenge associated with controlling ring-size selectivity. Here we describe the catalytic reductive cocyclooligomerization of an enone and three carbene equivalents to generate a cyclopentane, a process that constitutes a formal [2 + 1 + 1 + 1]-cycloaddition. The reaction is promoted by a (quinox)Ni catalyst and uses CH2Cl2/Zn as the C1 component. Mechanistic studies are consistent with a metallacycle-based pathway, featuring sequential migratory insertions of multiple carbene equivalents to yield cycloalkanes larger than cyclopropanes.
Synthesis of trifluoromethyl-/cyclopropyl-substituted 2-isoxazolines by DBU-promoted domino reaction
Liu, Xiao-Dong,Ma, Hai-Yan,Xing, Chun-Hui,Lu, Long
supporting information, p. 1780 - 1783 (2017/07/27)
NTrifluoromethyl and cyclopropyl substituted 2-isoxazolines were synthesized via a DBU-promoted domino reaction of β-trifluoromethyl-/β-cyclopropyl-substituted enones with hydroxylamine. The domino reaction consists of a Michael addition and the followed cyclization. A wide range of 3-substituted 5-cyclopropyl-5- trifluoromethyl-2-isoxazolines were obtained in good to excellent yields under mild reaction conditions. The method could also apply to other trifluoromethyl-substituted enones.
Design and synthesis of 3-trifluoromethyl-3h-pyrazoles and further investigations of their transformation to 1h-pyrazoles
Sha, Qiang,Liu, Haixuan,Wei, Yunyang
, p. 7707 - 7715 (2015/04/22)
An efficient intramolecular cycloaddition strategy for the synthesis of trifluoromethyl-substituted 3H-pyrazoles was developed. Subsequently, their wide applications were demonstrated: they (1) react with dioxane by a radical process and (2) undergo [1,5] sigmatropic rearrangements. These applications are useful as the products were obtained in high yields and with excellent regioselectivity.
Identification of novel chromenone derivatives as interleukin-5 inhibitors
Venkateswararao, Eeda,Kim, Min-Seok,Sharma, Vinay K.,Lee, Ki-Cheul,Subramanian, Santhosh,Roh, Eunmiri,Kim, Youngsoo,Jung, Sang-Hun
, p. 31 - 38 (2013/03/13)
A series of (E)-5-alkoxy-3-(3-phenyl-3-oxoprop-1-enyl)-4H-chromen-4-ones (4) and (E)-5-alkoxy-3-(3-hydroxy-3-phenylprop-1-enyl)-4H-chromen-4-ones (5) were synthesized and evaluated for their IL-5 inhibitory activity. Propenone analogs 4 possess some of the structurally important characteristics of isoflavone 2 and chalcone 3 previously known as potent IL-5 inhibitor. However, the inhibitory activity of 4 was weak and therefore this structural hybridization appears to be ineffective for the design of IL-5 inhibitor. Meanwhile the potent activity profile of compounds 5 was discovered. This enhanced activity of 5 compared to 4 could be due to the effective location of hydroxyl group of allylic alcohol moiety of 5 in the 3D structure. The electron withdrawing substituents at position 4 of phenyl ring of 5 enhances the activity possibly due to an increase in the strength of hydrogen bonding property of hydroxyl group of allylic alcohol moiety.
