21524-18-5 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 21524-18-5 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,1,5,2 and 4 respectively; the second part has 2 digits, 1 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 21524-18:
(7*2)+(6*1)+(5*5)+(4*2)+(3*4)+(2*1)+(1*8)=75
75 % 10 = 5
So 21524-18-5 is a valid CAS Registry Number.
21524-18-5Relevant articles and documents
Synthesis and Structure of Phenylazohydroquinones
Pardo, Mercedes,Joos, Karlheinz,Schaefer, Wolfram
, p. 99 - 111 (2007/10/02)
Phenylazohydroquinones 3, 4 (and not hydrazinoquinones) have been synthesized from 2,5-bis(arylamino)-1,4-benzoquinone-3-carboxylic acids 1 and hydrazines 2; the structure of 3 and 4 was confirmed by spectroscopic (IR, UV, 1H-NMR, and 13C-NMR) data.