Abstract A facile protocol to the chemoselective deprotection of aryl t-butyldimethylsilyl (TBDMS) ethers using Na3PO4 · 12H2O as promoter is described. From aryl TBDMS ethers to the corresponding phenols, the TBDMS group could be cleaved in the presence of 0.5 equivalent of Na3PO4 · 12H2O in dimethylformamide at room temperature with good to excellent yields in the presence of other common protecting
ZnAl2O4–Bi2O3 composite nano-powder as an efficient catalyst for the multi-component, one-pot, aqueous media preparation of novel 4H-chromene-3-carbonitriles
作者:Majid Ghashang
DOI:10.1007/s11164-015-2269-x
日期:2016.5
A composite structure of ZnAl2O4–Bi2O3 nanopowder was prepared from the reaction of a watery solution of Zn(NO3)2, Al(NO3)3, and Bi(NO3)3 with a dilute solution of amino ethanol in water via a simple precipitation-complexation method. The as-prepared composite was used for the one-pot synthesis of 2-amino-4-aryl-7-(pyrrolidin-1-yl)-4H-chromene-3-carbonitrile, 2-amino-4-aryl-7-(piperidin-1-yl)-4H-chromene-3-carbonitrile, 2-amino-4-aryl-7-(1H-pyrrol-1-yl)-4H-chromene-3-carbonitrile, 2-amino-4-aryl-6-(2-(piperidin-1-yl)ethyl)-4H-chromene-3-carbonitrile and 2-amino-4-aryl-6-(1H-pyrrol-1-yl)-4H-chromene-3-carbonitrile derivatives. This procedure is very simple and affords excellent yields.
Solvent-Mediated Enantioselective Rauhut–Currier Cyclization via Iminium and Enamine Activation
作者:Satish B. Thopate、Lakshmi Revati Magham、Shrabani Dinda、Rambabu Chegondi
DOI:10.1021/acs.orglett.2c04249
日期:2023.2.24
an unconventional and highly enantioselective solvent-promoted Rauhut–Currier cyclization of enal-tethered cyclohexadienone by exploiting the reactivity of a simple Jørgensen–Hayashi catalyst through the merging of iminium and enamine activation. This asymmetricdesymmetrizationreaction has broad substrate scope in good yields with high to excellent enantioselectivity. DFT calculations suggest that
REAGENTS FOR LABELING SH GROUPS, PROCESS FOR THE PREPARATION OF THEM, AND METHOD FOR LABELING WITH THEM
申请人:SS Pharmaceutical Co., Ltd.
公开号:EP0844246A1
公开(公告)日:1998-05-27
Disclosed are SH-labeling reagents containing acridine compounds represented by the following formula (I):
wherein
A represents the following group:
-(CH2)m1-
or
-(CH2)m2-Q-(CH2)n-
in which Q represents a group -S+RX--, a group -N+RR1X-- wherein R1 represents an alkyl group having 1 to 6 carbon atoms or an aryl group, a group
wherein R2 and R3 may be the same or different and are each independently a group -(CH2)k- (k: a number of 1 to 3) or -O(CH2CH2O)ℓ- (ℓ: a number of 1 to 3),
m1 stands for a number of 1 to 6,
m2 denotes a number of 0 to 2,
n means a number of 1 to 2;
R represents an alkyl group having 1 to 6 carbon atoms or an aryl group; and
X- represents an anion, or intermediates thereof; preparation processes of the acridine compounds; and methods for labeling analytes by using the compounds.