Antimycobacterial Compounds from Piper sanctum

Abstract

Bioassay-guided chromatographic separation of the antimycobacterial extract of the leaves of Piper sanctum afforded 14 new compounds, identified as 2-oxo-12-(3',4'-methylenedioxyphenyl)dodecane (1), 2-oxo-14-(3',4'-methylenedioxyphenyl)tetradecane (2), 2-oxo-16-(3',4'-methylenedioxyphenyl)hexadecane (3), 2-oxo-18-(3',4'-methylenedioxyphenyl)octadecane (4), 2-oxo-14-(3',4'-methylenedioxyphenyl)-trans-13-tetradecene (5), 2-oxo-16-(3',4'-methylenedioxyphenyl)-trans-15-hexadecene (6), 2-oxo-18-(3',4'-methylenedioxyphenyl)-trans-17-octadecene (7), 2-oxo-16-phenyl-trans-3-hexadecene (8), methyl [6-(10-phenyldecanyl)tetrahydropyran-2-yl]acetate (9), methyl 2-(6-tridecyltetrahydro-2H-pyran-2-yl)acetate (10), methyl 2-(5-tetradecyltetrahydro-2-furanyl)acetate (11), 2-oxo-14-(3',4'-methylenedioxyphenyl)-trans-3-tetradecene (12), 2-oxo-16-(3',4'-methylenedioxyphenyl)-trans-3-hexadecene (13), and 2-oxo-16-phenyl-3-hexadecane (14). In addition, p-eugenol (15), methyleugenol (16), Z-piperolide (17), demethoxyyangonin (18), 5,6-dehydro-7,8-dihydromethysticin (19), cepharanone B (20), piperolactam A (21), cepharadione B (22), N-trans-feruloyltyramine (23), and N-trans-(p-coumaroyl)tyramine (24) were obtained from the anti-TBC stem extract of the plant. GC-MS and HPLC analyses of the essential oils of the leaves and stem revealed that safrol (25) was the major component of the oils. Compounds 2, 3, 6, 18-21, and 24 inhibited the growth of Mycobacterium tuberculosis when tested by the MABA assay, with MIC values ranging from 4 to 64 microg/mL.

Plants: A Source for New Antimycobacterial Drugs

“…(25 µg/mL) (6.25-50 µg/mL) [42] 2,4-undecadienal (25 µg/mL) (25-50 µg/mL) [46] mono-O-methylcurcumin isoxazole (0.09 µg/mL) (0.195-3.125 µg/mL) [67] Nummularine H (IC 50 − 4.5 µM) [13] (2S)-naringenin (< 2.8 µg/mL) [20] shinanolone (100 µg/mL) [36] beilschmin A (2.5 µg/mL) [43] kaurenoic acid (50 µg/mL) [48] 5,6-dehydro-7,8-dihydromethysticin (4 µg/mL) [68] prunetin (30 µg/mL) [20] 7-methyljuglone (0.5 µg/mL) [37] beilschmin B (7.5 µg/mL) [43] 1α-acetoxy-6β,9β-dibenzoyloxy-dihydro-β-agarofuran (> 25 µg/mL) (6.2 µg/mL) [50] piperolactam A (8 µg/mL) [68] (2S)-5,7,2′-trihydroxy flavonone (367.6 µM) [21] isodiospyrol A (50 µg/mL) [39] (…”

Kavalactones and Benzoic Acid Derivatives from Leaves of Piper fuligineum Kunth (Piperaceae)

“…The known compounds were identified as (E)-4-methoxy-6-styryl-2H-pyran-2-one (1), 25,26,31 4-methoxy-6-(3-phenyloxiran-2-yl)-2H-pyran-2-one (2), 6-(1,2-dihydroxy-2-phenylethyl)-4-methoxy-2H-pyran-2-one (3), 24 methyl-4-methoxy-3-(3'-methyl-2'-butenyl) benzoate (4) 32,33 and methyl 2,2-dimethyl-4-oxochroman-6-carboxylate (5) by NMR and/or by HRMS (Supplementary Information) as well as by comparison with the literature data. 13,14,24,34,35 The molecular formula of 6 was established as C 14 C NMR data corroborated the substituents of aromatic ring, and all signals were assigned accordingly based on the gHMBC data (Table 1).…”

Estratégias para a síntese de γ-alquilidenobutenolídeos

“…Essa transformação é sinteticamente útil uma vez que certos galquilidenobutenolídeos, como o piperolídeo 30 e seu epóxi-derivado 30 (Figura 4), são desprovidos de substituintes na posição alfa. Reações de ciclização entre enol éteres de silício e cloreto de oxalila também são úteis para a síntese de ésteres, análogos aos ácidos pulvínicos e vulpínicos.…”

“…9 Outros exemplos dessa classe de butenolídeos são os compostos 29-31. A substância 29 é conhecida por ativar a germinação de sementes, 13 enquanto a pirroxantina (30) 14 e peridinina (31) 15 correspondem aos g-alquilidenobutenolídeos de maior complexidade estrutural já isolados e desempenham papel importante na fotossíntese de algas e dinoflagelados, respectivamente.Os g-alquilidenobutenolídeos têm sido considerados atrativos alvos sintéticos devido à diversidade estrutural que apresentam, bem como às suas propriedades biológicas. Como consequência, vários procedimentos sintéticos vêm sendo desenvolvidos para o preparo dessas substâncias.…”

“…9 Outros exemplos dessa classe de butenolídeos são os compostos 29-31. A substância 29 é conhecida por ativar a germinação de sementes, 13 enquanto a pirroxantina (30) 14 e peridinina (31) 15 correspondem aos g-alquilidenobutenolídeos de maior complexidade estrutural já isolados e desempenham papel importante na fotossíntese de algas e dinoflagelados, respectivamente.…”