128256-21-3 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 128256-21-3 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,8,2,5 and 6 respectively; the second part has 2 digits, 2 and 1 respectively.
Calculate Digit Verification of CAS Registry Number 128256-21:
(8*1)+(7*2)+(6*8)+(5*2)+(4*5)+(3*6)+(2*2)+(1*1)=123
123 % 10 = 3
So 128256-21-3 is a valid CAS Registry Number.
128256-21-3Relevant articles and documents
A convenient synthesis of Quinazoline ring by tandem aza-Wittig reaction/electrocyclic ring closure
Rossi,Calabrese,Farma
, p. 5819 - 5834 (2007/10/02)
3,4-D-Dihydroquinazolines and Quinazolines were prepared starting from N'-aryl-N-(triphenylphosphoranilidene)-carboximidamides and aliphatic or aromatic aldehydes. The mechanism of the reaction is discussed.