Synthesis and Pharmacological Activity of Betulin Dinicotinate

The assignment of NMR resonances of lupane triterpenoids was refined by the example of 3O,28O-dinicotinoylbetulin, obtained by acylation of betulin. Hepatoprotective, antiulcer, antiinflammatory, reparative, and anti-HIV activities were found for the compound. In addition, it was demonstrated to have immunomodulatory activity, for the first time detected among lupane triterpenoids.     

The synthesis and hepatoprotective activity of esters of the lupane group triterpenoids

Hemisuccinates, hemiphthalates, acetylsalicylates, cinnamates, andp-methoxycinnamates of lupeol, betulin, and 3-O-acetylbetulin were synthesized via interaction with corresponding acid anhydrides or acid chlorides. A number of betulin esters in position 3 and 28 were shown to exhibit a pronounced hepatoprotective effect similar to that of betulin and silibor. These experimental data were in a good agreement with the computer prediction of their biological activity. Betulin 3,28-bishemiphthalate was more effective than carsil in models of experimental hepatitis caused by carbon tetrachloride, tetracycline, and ethanol.     

A complex of pyridine and phosphatidylcholine

The effect of pyridine on the electronic structure and conformational state of cell phosphatidylcholine was studied by the methods of quantum chemistry and 13C NMR spectroscopy. It was shown that the interaction of the pi-system of pyridine electrons with the choline group of phosphatidylcholine leads to the formation of a complex. Changes in the conformational states due to the formation of this complex were revealed.     

Transformation of betulin diacetate by the Prins reaction

The interaction of betulin diacetate with formaldehyde by the Prins reaction in various media was studied. As a result, 3β,28-di-O-acetyl-30-hydroxymethyl-(20)29-lupene, 3β-acetyl-28-hydroxy-(20)29-lupene, and 3β,28-di-O-acetoxy-19-(5′,6′-dihydro-2′H-pyran-4′-yl)-20,29,30-trinorlupane were obtained.     

Synthesis and pharmacological activity of betulin dinicotinate

The assignment of NMR resonances of lupane triterpenoids was refined by the example of 3,28-dinicotinoylbetulin, obtained by acylation of betulin. Hepatoprotective, untiulcer, antiinflammatory, reparative, and anti-HIV activities were found for the compound. In addition, it was demonstrated to have immunomodulatory activity, for the first time detected among lupane triterpenoids. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2002, vol. 28, no. 6; see also http://www.maik.ru.     

Synthesis and antiviral activity of lupane triterpenoids with modified cycle E

A reductive transformation of the peroxide products of ozonolysis of derivatives of 3beta-O-acetyl-22(17-->28)-abeo-lupa-17(28),20(29)-diene and the subsequent intramolecular ketalization led to a compound with a trioxane fragment. This is a new approach to a skeletal modification of triterpenoid cycle E. An activity of the synthesized compounds was found toward the viruses of type A influenza and herpes simplex.     

The synthesis and anti-inflammatory activity of quinopimaric acid derivatives

Under the action of PCl₅, the Beckman rearrangement of a 3: 1 mixture of Z- and E-isomeres of 18β-hydro-xydihydroquinopimaric acid resulted in 5′-caprolactam and isomeric caprolactams containing fragments of cyclic ether. Z- and E-ketoximes were separated as acetates. Using a carrageenan inflammation model, we demonstrated that the anti-inflammatory activity of quinopimaric acid derivatives was comparable with that of diclofenac.     

Synthesis and antiviral activity of lupane triterpenoids with modified cycle E

A reductive transformation of the peroxide products of ozonolysis of derivatives of 3β-O-acetyl-22(17→28)-abeo-lupa-17(28),20(29)-diene and the subsequent intramolecular ketalization led to a compound with a trioxane fragment. This is a new approach to a skeletal modification of triterpenoid cycle E. An activity of the synthesized compounds was found toward the viruses of type A influenza and herpes simplex.     

Uraline,a New Norditerpenoid Alkaloid from Aerial Parts of <Emphasis Type="Italic">Delphinium uralense</Emphasis> Nevski

Uraline, a new norditerpenoid alkaloid, was isolated from aerial parts of Delphinium uralense. The structure of 1α,7,8-trihydroxy-6β,14α,16β-trimethoxy-18-N-(2-methyl)succinylanthranoyloxyaconane was ascribed to the new compound on the basis of ¹H and ¹³C NMR, IR, and mass spectra. The known alkaloids methyllycaconitine and delcorine were also isolated from the plant.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 4, 2005, pp. 425–429.Original Russian Text Copyright © 2005 by Gabbasov, Tsyrlina, Spirikhin, Danilov, Yunusov.     

Uraline, a new norditerpenoid alkaloid from aerial parts of Delphinium uralense nevski

Uraline, a new norditerpenoid alkaloid, was isolated from aerial parts of Delphinium uralense. The structure of 1alpha,7,8-trihydroxy-6beta,14alpha,16beta-trimethoxy-18-N-(2-methyl)succinylanthranoyloxyaconane was ascribed to the new compound on the basis of 1H and 13C NMR, IR, and mass spectra. The known alkaloids methyllycaconitine and delcorine were also isolated from the plant.