25991-81-5 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 25991-81-5 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,5,9,9 and 1 respectively; the second part has 2 digits, 8 and 1 respectively.
Calculate Digit Verification of CAS Registry Number 25991-81:
(7*2)+(6*5)+(5*9)+(4*9)+(3*1)+(2*8)+(1*1)=145
145 % 10 = 5
So 25991-81-5 is a valid CAS Registry Number.
InChI:InChI=1/C15H12O6/c1-19-10-4-3-9-13(15(10)20-2)14(18)12-8(17)5-7(16)6-11(12)21-9/h3-6,16-17H,1-2H3
25991-81-5Relevant articles and documents
Method for preparing 1,3,5,8-tetrahydroxy xanthone and 1,3,7,8-tetrahydroxy xanthone
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Sheet 0039; 0047-0049, (2019/09/14)
The invention discloses a method for preparing 1,3,5,8-tetrahydroxy xanthone and 1,3,7,8-tetrahydroxy xanthone. The method comprises the following steps: by taking 1,2,4-trimetoxybenzene as an initialraw material, and adding n-butyllithium and a chloro-ca