203189-41-7 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 203189-41-7 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 2,0,3,1,8 and 9 respectively; the second part has 2 digits, 4 and 1 respectively.
Calculate Digit Verification of CAS Registry Number 203189-41:
(8*2)+(7*0)+(6*3)+(5*1)+(4*8)+(3*9)+(2*4)+(1*1)=107
107 % 10 = 7
So 203189-41-7 is a valid CAS Registry Number.
203189-41-7Relevant articles and documents
A convenient synthesis of 2,3,4,5-functionalised thieno[2,3-b]thiophenes
Sommen, Geoffroy,Comel, Alain,Kirsch, Gilbert
, p. 735 - 741 (2007/10/03)
A two steps simple synthesis of 2,3,4,5-functionalised thieno[2,3-b]thiophenes 2-6 from ketene dimethylthioacetals is described.
