177657-33-9 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 177657-33-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,7,7,6,5 and 7 respectively; the second part has 2 digits, 3 and 3 respectively.
Calculate Digit Verification of CAS Registry Number 177657-33:
(8*1)+(7*7)+(6*7)+(5*6)+(4*5)+(3*7)+(2*3)+(1*3)=179
179 % 10 = 9
So 177657-33-9 is a valid CAS Registry Number.
177657-33-9Relevant articles and documents
Synthesis of α-amino dithioesters and endothiodipeptides
Hartke, Klaus,Barrmeyer, Stephan
, p. 251 - 256 (2007/10/03)
The α-amino ester hydrochlorides (1) are converted into N-protected α-amino amides (3), α-amino thioamides (4) and α-amino dithiomethylesters (5). Condensation of 5 with the alkali salts of α-amino acids gives rise to the endothiodipeptide alkali salts (7). Johann Ambrosius Barth 1996.