57544-20-4 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 57544-20-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 5,7,5,4 and 4 respectively; the second part has 2 digits, 2 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 57544-20:
(7*5)+(6*7)+(5*5)+(4*4)+(3*4)+(2*2)+(1*0)=134
134 % 10 = 4
So 57544-20-4 is a valid CAS Registry Number.
InChI:InChI=1/C16H12ClNO4/c1-21-13-6-7-15-11(8-13)9-14(18(19)20)16(22-15)10-2-4-12(17)5-3-10/h2-9,16H,1H3
57544-20-4Relevant articles and documents
Augmentation of Enantioselectivity by Spatial Tuning of Aminocatalyst: Synthesis of 2-Alkyl/aryl-3-nitro-2 H-chromenes by Tandem Oxa-Michael-Henry Reaction
Bez, Ghanashyam,Mohanta, Rahul
, p. 4627 - 4636 (2020/05/01)
The asymmetric oxa-Michael addition of salicylaldehyde to conjugated nitroalkenes often suffers from poor reactivity and selectivity and a long reaction time. Because of the formation of an iminium ion with aminocatalyst, the nucleophilicity of the phenol