New Triterpenes of Lantana camara. A Comparative Study of the Constituents of Several Taxa

1976 ◽  
Vol 29 (3) ◽  
pp. 655 ◽  
Author(s):  
N Hart ◽  
J Lamberton ◽  
A Sioumis ◽  
H Suares
Keyword(s):  
Comparative Study ◽  
Major Product ◽  
Lantana Camara ◽  
Betulonic Acid ◽  
Triterpene Acids ◽  
Lantadene A ◽  
Derivatives Of

The triterpenes of Lantana camara vary widely between taxa. In taxa toxic to livestock 22β-angeloyloxy-3-oxoolean-12-en-28-oic acid (lantadene A) and 22β-dimethylacryloyloxy-3-oxoolean-12-en-28- oic acid (lantadene B) are present, usually as major constituents, although 3-oxolup-20(29)-en-28-oic acid (betulonic acid) predominates in the taxon Helidon White. 22β-Angeloyloxy-3β-hydroxyolean- 12-en-28-oic acid, 22β -dimethylacryloyloxy-3β -hydroxyolean-12-en-28-oic acid and 22β-hydroxy-3-oxoolean-12-en-28-oic acid, not previously known to occur in L. camara, have been isolated as well as a number of other well-known triterpenes. The non-toxic Townsville Prickly Orange contains small amounts of lantadenes A and B, and is the only taxon found to contain 228-angeloyloxy-23- hydroxy-3-oxoo1ean-12-en-28-oic acid (icterogenin). Another constituent is the new triterpene 24-hydroxy-3-oxoolean-12-en-28-oic acid. Common Pink, which is non-toxic and does not contain lantadenes A and B, is characterized by triterpene acids which have a C3, C25 oxide-bridge. It contains lantanolic acid, lantic acid, and a new acid, lantabetulic acid, considered to be 3,25-epoxy- 3a-hydroxylup-20(29)-en-28-oic acid. A mixture of the 22β-angeloyloxy and 22β-dimethylacryloyloxy derivatives of lantanolic acid from Common Pink has been converted into 22P-hydroxylantanolic acid. Wolff-Kishner reduction of 22~-hydroxy-3-oxoolean-12-en-28-oic acid gives a low yield of 22β-hydroxyolean-12-en-28-oic acid, and the major product is the C22-epimer, 22a-hydroxyolean- 12-en-28-oic acid. Corresponding products are obtained from Wolff-Kishner reduction of 22β- hydroxylantanolic acid.

scholarly journals Synthesis and Evaluation of Anticancer Activities of Novel C-28 Guanidine-Functionalized Triterpene Acid Derivatives

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 3000 ◽  
Author(s):  
Anna Spivak ◽  
Rezeda Khalitova ◽  
Darya Nedopekina ◽  
Lilya Dzhemileva ◽  
Milyausha Yunusbaeva ◽  
...  
Keyword(s):  
Human Fibroblasts ◽  
Human Tumor ◽  
Jurkat Cells ◽  
Anticancer Activities ◽  
Triterpene Acid ◽  
Guanidine Group ◽  
Triterpene Acids ◽  
Cycle Arrest ◽  
Normal Human ◽  
Derivatives Of

Triterpene acids, namely, 20,29-dihydrobetulinic acid (BA), ursolic acid (UA) and oleanolic acid (OA) were converted into C-28-amino-functionalized triterpenoids 4–7, 8a, 15, 18 and 20. These compounds served as precursors for the synthesis of novel guanidine-functionalized triterpene acid derivatives 9b–12b, 15c, 18c and 20c. The influence of the guanidine group on the antitumor properties of triterpenoids was investigated. The cytotoxicity was tested on five human tumor cell lines (Jurkat, K562, U937, HEK, and Hela), and compared with the tests on normal human fibroblasts. The antitumor activities of the most tested guanidine derivatives was lower, than that of corresponding amines, but triterpenoids with the guanidine group were less toxic towards human fibroblasts. The introduction of the tris(hydroxymethyl)aminomethane moiety into the molecules of triterpene acids markedly enhanced the cytotoxic activity of the resulting conjugates 15, 15c, 18b,c and 20b,c irrespective of the triterpene skeleton type. The dihydrobetulinic acid amine 15, its guanidinium derivative 15c and guanidinium derivatives of ursolic and oleanolic acids 18c and 20c were selected for extended biological investigations in Jurkat cells, which demonstrated that the antitumor activity of these compounds is mediated by induction of cell cycle arrest at the S-phase and apoptosis.

Bromination of Tetralin. Short and Efficient Synthesis of 1,4-Dibromonaphthalene

2000 ◽  
Vol 65 (11) ◽  
pp. 1791-1804 ◽  
Author(s):  
Osman Çakmak ◽  
Ismail Kahveci ◽  
Íbrahim Demirtaş ◽  
Tuncer Hökelek ◽  
Keith Smith
Keyword(s):  
High Temperature ◽  
Major Product ◽  
High Yield ◽  
Efficient Synthesis ◽  
Secondary Products ◽  
Derivatives Of ◽  
Sole Product

High-temperature bromination of tetralin (1,2,3,4-tetrahydronaphthalene) with bromine resulted in benzylic bromination to give 1,4-dibromo-1,2,3,4-tetrahydronaphthalene (4) as a major product and several secondary products. Photolytic bromination of tetralin and subsequent double dehydrobromination of 1,1,4,4-tetrabromo-1,2,3,4-tetrahydronaphthalene (10) gave 1,4-dibromonaphthalene (11) as the sole product in a high yield. 1,4-Dibromonaphthalene is efficiently converted to the corresponding methoxy (12 and 13) and cyano (14 and 15) derivatives of naphthalene.

Comparative study of dG affinity vs. DNA methylation modulating properties of side chain derivatives of procainamide: insight into its DNA hypomethylating effect

RSC Advances ◽  
2016 ◽  
Vol 6 (7) ◽  
pp. 5350-5358 ◽  
Author(s):  
R. L. Gawade ◽  
D. K. Chakravarty ◽  
J. Debgupta ◽  
E. Sangtani ◽  
S. Narwade ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Comparative Study ◽  
Structural Features ◽  
Side Chain ◽  
Side Chains ◽  
Hypomethylating Agents ◽  
Derivatives Of ◽  
Insight Into

Structural features of side-chains govern the association of procainamide and its derivatives with dG base of CpG rich DNA, which may differentially hinder the activity of DNMT-1, thereby they act as DNA hypomethylating agents.

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