Stereoselective and Regioselective Assembly of Spirooxindole [2,1-<i>b</i>]furan Motifs through a Tandem Friedel-Crafts Alkylation/5-<i>exo</i>-<i>dig</i>-Cyclization
作者:Nandarapu Kumarswamyreddy、Venkitasamy Kesavan
DOI:10.1002/ejoc.201601030
日期:2016.11
3-Alkynyl-3-OBoc (Boc = tert-butoxycarbonyl) oxindole derivatives underwent a CuII-mediated stereo- and regioselectiveFriedel–Crafts alkylation/5-exo-dig-cyclization with 2-naphthols or cyclic 1,3-diketones. This gave spirooxindole [2,1-b]furan motifs in good to excellent yields under ambient conditions, and the process has a wide substrate scope.
Mushroom Tyrosinase Inhibition Activity of Some Chromones.
作者:Long Zhu Piao、Hyang Rae Park、Yun Kyung Park、Seung Ki Lee、Jeong Hill Park、Man Ki Park
DOI:10.1248/cpb.50.309
日期:——
Currently, aloesin is used in the cosmetic industry as a whitening agent because it inhibits tyrosinase activity. Aloesin is a C-glycosylated chromone compound isolated fromaloe, and it is difficult to synthesize because of C-glycosyl moiety in the molecule. The purpose of this study is to search for a new chromone compound which is easy to synthesize and which posesses stronger tyrosinase inhibitory
Conformation and<i>ortho</i>steric effects in a series of 2-(pyrazol-1-yl)quinolines
作者:Shiv P. Singh、Dalip Kumar、Devinder Kumar、Ana Martínez、José Elguero
DOI:10.1002/jhet.5570330219
日期:1996.3
The 1H and 13C chemical shifts were discussed taking into account the preferred conformation about the C-2-N-1′ bond as calculated by the AM1 Hamiltonian. It appears that 5-ethyl and 5-isopropyl substituted derivatives present short C-H-N-1 interactions. Ortho stericeffects appear to be responsible for these conformations.
Catechol derivatives, their physiologically acceptable salts, esters and
申请人:Orion-yhtyma Oy
公开号:US05489614A1
公开(公告)日:1996-02-06
Known and new catechol derivates may be used as medicinal antioxidants in the prevention or treatment of tissue damage induced by lipid peroxidation. The conditions and diseases to be treated are for example heart disease, rheumatoid arthritis, cancer, inflammatory disease, a rejection reaction in organ transplants, ischemia, cancer and aging.