18708-54-8Relevant articles and documents
Asymmetric Radical Process for General Synthesis of Chiral Heteroaryl Cyclopropanes
Deb, Arghya,Ke, Jing,Wang, Xiaoxu,Xu, Yijie,Zhang, X. Peter,Zhu, Yiling
supporting information, p. 11121 - 11129 (2021/08/03)
A highly efficient catalytic method has been developed for asymmetric radical cyclopropanation of alkenes with in situ-generated α-heteroaryldiazomethanes via Co(II)-based metalloradical catalysis (MRC). Through fine-tuning the cavity-like environments of newly-synthesized D2-symmetric chiral amidoporphyrins as the supporting ligand, the optimized Co(II)-based metalloradical system is broadly applicable to α-pyridyl and other α-heteroaryldiazomethanes for asymmetric cyclopropanation of wide-ranging alkenes, including several types of challenging substrates. This new catalytic methodology provides a general access to valuable chiral heteroaryl cyclopropanes in high yields with excellent both diastereoselectivities and enantioselectivities. Combined computational and experimental studies further support the underlying stepwise radical mechanism of the Co(II)-based olefin cyclopropanation involving α- and γ-metalloalkyl radicals as the key intermediates.
Substituent-Oriented Synthesis of Substituted Pyrazoles/Chromeno[3,2- c]pyrazoles via Sequential Reactions of Chromones/3-Chlorochromones and Tosylhydrazones
Dai, Tianzi,Li, Qunyi,Zhang, Xiaofei,Yang, Chunhao
, p. 5913 - 5921 (2019/05/10)
A facile and efficient synthetic strategy for the chemoselective synthesis of monocyclic/tricyclic-fused pyrazoles was developed, and it was oriented by different 3-position substituents (H or Cl) on the chromones. The reaction proceeded in a one-pot sequential way with a broad substrate scope and moderate to excellent yields.
Antineoplastic and biochemical properties of arylsulfonylhydrazones of 2 formylpyridine N oxide
Sartorelli,Agrawal,Booth,Pittman,Bartholomew
, p. 830 - 833 (2007/10/05)
The structural parameters necessary for the antineoplastic potency of a new class of anticancer agents, arylsulfonylhydrazones of 2 formylpyridine N oxide, were examined in mice bearing Sarcoma 180 ascites cells. The findings indicated that (a) replacement of the pyridine ring with benzene quinoline, or isoquinoline resulted in loss of activity, (b) movement of the formylhydrazone side chain from the 2 to the 3 or 4 positions of the pyridine N oxide produced inactive agents, (c) the pyridine N oxide function was essential for anticancer activity, except for 4 substituted derivatives which were active without the N oxide group, (d) replacement of the SO2 group by CO resulted in complete loss of activity, and (e) a carbon atom could be inserted between the SO2 and aryl ring with retention of anticancer potency. One of the most active members of this series, 1 oxidopyridine 2 carboxaldehyde p toluenesulfonylhydrazone exhibited antineoplastic, activity against a broad spectrum of transplanted tumors including Sarcoma 180, Hepatoma 129, Ehrlich carcinoma, leukemia L1210, and a subline of Sarcoma 180 resistant to α (N) heterocyclic carboxaldehyde thiosemicarbazones. This agent caused inhibition of thymidine 3H and uridine 3H incorporation into DNA and RNA respectively, of Sarcoma 180 ascites cells; protein biosynthesis was relatively insensitive to the action of this compound.