Triterpenoidal alkaloids from Buxus hyrcana and their enzyme inhibitory, anti-fungal and anti-leishmanial activities

Bioactive steroidal alkaloids from Buxus macowanii Oliv.

“…The methoxy protons (d 3.91) showed an NOE with the C-2 0 methine proton (d 7.47) suggesting its substitution at C-3 0 . The NOESY spectrum of 5 indicated the same stereochemistry at all chiral centers as those of previously discussed compounds (1)(2)(3)(4) and other reported Buxus alkaloid [1][2][3][4][5][28][29][30]. H-10 (d 1.19) showed NOE with H-8 (d 2.25) and H 3 -30 (d 0.98) suggesting its b-orientation.…”

“…Its UV spectrum showed maximum absorption at 218 nm suggesting the presence of a benzamide chromophore [1][2][3][28][29][30]. The IR spectrum displayed absorption bands at 3383 (OH), 2945 (CH), and 1667 (amide C@O) cm À1 .…”

“…Compound 6 was previously isolated from the root of B. papillosa [31] while compound 7 was purified from B. papillosa [32][33][34]37], Buxus hildebrandtii [35], Buxus rugulosa [36] and B. hyrcana [3,38], and compounds 8, 9 and 10 were previously reported from B. hyrcana [2], Buxus bodinieri [39] and B. microphylla [40], respectively.…”

“…Previous phytochemical studies on various plants of this genus, including Buxus papillosa, Buxus microphylla, Buxus hyrcana, Buxus natalensis and others, have resulted in the isolation of over 200 steroidal alkaloids [1][2][3][4][5][6]. A few of these alkaloids are reported to exhibit various biological activities including antimicrobial, anti-tuberculosis, and anti-acetylcholinesterase activities [1][2][3][4][5][6]. Buxus macowanii Oliv., commonly known as Cape Box, is a small growing evergreen tree which is native to Eastern Cape Forest of South Africa.…”

Natural AChE Inhibitors from Plants and their Contribution to Alzheimer’s Disease Therapy

“…Three new triterpenoidal alkaloids, namely 17-oxo-3-benzoylbuxadine ( 106 ), buxhyrcamine ( 107 ) and 31-demethylcyclobuxoviridine ( 108 ) along with sixteen known compounds, all tested as AChEi, were isolated and characterized in a recent study on B. hyrcana collected from Iran [50]. Weak AChE inhibitory activity was observed for N b -dimethylcyclobuxoviricine ( 109 ), papillozine C ( 110 ), cyclobuxophylline O ( 111 ) and arbora-1,9(11)-dien-3-one ( 112 ) (IC 50 = 35.4 - 47.9 µM).…”