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Updated: May 4, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
[Synthesis of aminopropylaminoderivatives of betulinic and oleanolic acids]
Abstract:
On the basis of betulinic and oleanolic acids triterpenoids with different with different amine fragments: (3-aminopropoxy)-, 3-acetyl-(3-aminopropyl)amino-, 6-[bis(3-aminopropyl)amino]hexylamino-, (3-aminopropyl)-4-aminosulfonyl-4-phenylamino- at positions C3 and C28 were synthesized. It is shown that betulonic acid amide with 4,4'-diaminodiphenylsulfonic substituent don't render antitumor effect in mice with transplantable Lewis lung carcinoma, but possess significant anti-inflammatory activity.
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