201664-75-7 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 201664-75-7 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 2,0,1,6,6 and 4 respectively; the second part has 2 digits, 7 and 5 respectively.
Calculate Digit Verification of CAS Registry Number 201664-75:
(8*2)+(7*0)+(6*1)+(5*6)+(4*6)+(3*4)+(2*7)+(1*5)=107
107 % 10 = 7
So 201664-75-7 is a valid CAS Registry Number.
201664-75-7Relevant articles and documents
Heterocyclic synthesis by C-C bond formation. Thionium ion-mediated preparation of substituted pyrrolidines and piperidines
Craig, Donald,Meadows, James D.,Pecheux, Muriel
, p. 147 - 150 (2007/10/03)
Dithioacetal-S,S-dioxides 6 and 7 undergo cyclisation to give pyrrolidines and piperidines upon exposure to Lewis acid. An unexpected tandem cyclisation of 5 to give 10 is described.