"Z-D-Val-L-HyIv-Val-D-Lac-OtBu" is a peptide sequence consisting of seven amino acids, with Z being the protecting group, D and L indicating the chirality of the amino acids, and OtBu representing the tert-butyl protecting group. The sequence is composed of two D-valine (D-Val) residues, two L-valine (L-Val) residues, one L-hydroxyisovaline (L-HyIv), and one D-lactic acid (D-Lac). This specific arrangement of amino acids and protecting groups is crucial for the peptide's stability, solubility, and biological activity. The sequence is often used in the synthesis of bioactive peptides and pharmaceuticals, where the precise configuration of the amino acids and protecting groups can significantly impact the peptide's function and effectiveness.
The CAS Registry Mumber 31518-67-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,1,5,1 and 8 respectively; the second part has 2 digits, 6 and 7 respectively. Calculate Digit Verification of CAS Registry Number 31518-67: (7*3)+(6*1)+(5*5)+(4*1)+(3*8)+(2*6)+(1*7)=99 99 % 10 = 9 So 31518-67-9 is a valid CAS Registry Number.