Synthesis of phosphonodipeptide conjugates of ursolic acid and their homologs

Abstract

ABSTRACT:To prepare novel derivatives of naturally bioactive 3β-hydroxy-urs-12-en-28-oic acid (ursolic acid)

Phthalic anhydride (PA): a valuable substrate in organic transformations

“…In the second step (Scheme 117), the introduction of phosphonodipeptides and their homologs ( 305 ) to naturally bioactive ursolic acid (UA) ( 306 ) at C-28 moiety afforded new classes of phosphonodipeptide conjugates of ursolic acid and their homologs ( 309 ), which was performed by (i) its acylation to 3β-acetoy-urs-12-en-28-oic acid ( 307 ); (ii) chlorination to 3β-acetoy-urs-12-en-28-oyl chloride ( 308 ), and (iii) final reaction with ( 305 ) to afford the ( 309 ) adducts. 283 The phosphonodipeptide conjugates of UA and their homologs ( 309 ) are potent for anti-HT29 (human colon cancer cell line) and anti-HIV properties.…”

“…259 Jahanshahi and Mamaghani in 2019 described the synthesis of a wide range of novel 1H-pyrazolo[1,2-b]phthalazine-5,10-dioness (284) in the presence of acetic acid-functionalized imidazolium salt (1-carboxymethyl-2,3-dimethylimidazolium iodide, [cmdmim]I), as a newly synthesized Brønsted acid catalyst. The reaction occurred via tandem Knoevenagel cyclocondensation of PA (1), aromatic aldehydes (19), hydrazine hydrate (56), and 3-(1-methyl-1Hpyrrol-2-yl)-3-oxopropanenitrile (or 3-(1H-indol-3-yl)-3-oxopropanenitrile) (283) in the presence of [cmdmim]I in ethanol under reux conditions (Scheme 108). 260 The reusability of the catalyst was examined in 5 consecutive runs without any appreciable decrease in the activity.…”