Targeted Isolation of Anti-inflammatory Lignans from Justicia aequilabris by Molecular Networking Approach.

Herein, the isolation of secondary metabolites from the aerial parts of Justicia aequilabris guided by HPLC-MSn and molecular networking analyses is reported. Twenty-two known compounds were dereplicated. Three new lignans (aequilabrines A-C (1-3)) and three known compounds (lariciresinol-4'-O-ß-glucose (4), roseoside (5), and allantoin (6)) were obtained. The anti-inflammatory activity of compounds 1-3 was evaluated in vitro by inhibiting the nitric oxide production (NO) and pro-inflammatory activity on the cytokine IL-1ß. Compounds 2 and 3 showed significant inhibitory activity against NO production, with IC50 values of 9.1 and 7.3 µM, respectively. The maximum inhibition of IL-1ß production was 23.5% (1), 27.3% (2), and 32.5% (3).

A Novel Alkaloid Isolated from Spiranthera atlantica (Rutaceae).

A novel alkaloid 3-hydroxy-4-(2-hydroxyethyl)-4'-methoxy-7'H-quinolino[2,1-b]quinazolin-7'-one, named atlanticol (1), was isolated from Spiranthera atlantica (Rutaceae), along with five known compounds: lupeol (3), γ-fagarine (4), skimmianine (5), 7-methoxy-1-methyl-2-phenyl-4-quinolone (6) and 8-methoxy-1-methyl-2-phenyl-4-quinolone (7). Compound 6 was isolated from the Spiranthera genus for the first time. These compounds were characterized based on their spectral data, mainly through one and two-dimensional NMR and mass spectra, but also involving comparison with literature data.

First chemical constituents from Cordia exaltata Lam and antimicrobial activity of two neolignans.

The phytochemical study of Cordia exaltata Lam. (Boraginaceae) led to the isolation, through chromatographic techniques, of nineteen secondary metabolites: 8,8'dimethyl-3,4,3',4'-dimethylenedioxy-7-oxo-2,7'cyclolignan (1), 8,8'-dimethyl-4,5-dimethoxy-3',4'-methylenodioxy-7-oxo-2,7'cyclolignan (2), sitosterol (3a), stigmasterol (3b), sitosterol-3-O-ß-D-glucopyranoside (4a), stigmasterol-3-O-ß-D-glucopyranoside (4b), phaeophytin A (5), 13²-hydroxyphaeophytin A (6), 17³-ethoxypheophorbide A (7), 13²-hydroxy-17³-ethoxypheophorbide A (8), m-methoxy-p-hydroxybenzaldehyde (9), (E)-7-(3,4-dihydroxyphenyl)-7-propenoic acid (10), 1-benzopyran-2-one (11), 7-hydroxy-1-benzopyran-2-one (12), 2,5-bis-(3',4'-methylenedioxiphenyl)-3,4-dimethyltetrahydrofuran (13), 3,4,5,3',5'-pentamethoxy-1'-allyl-8.O.4'-neolignan (14), 3,5,7,3',4'-pentahydroxyflavonol (15), 5,7-dihydroxy-4'-methoxyflavone (16), 5,8-dihydroxy-7,4'-dimethoxyflavone (17), kaempherol 3-O-ß-D-glucosyl-6''-α-L-ramnopyranoside (18) and kaempherol 3,7-di-O-α-L-ramnopyranoside (19). Their structures were identified by ¹H and ¹³C-NMR using one and two-dimensional techniques. In addition, the antimicrobial activity of compounds 1, 2, 13 and 14 against bacteria and fungi are reported here for the first time.

Chemical composition of Aspidosperma ulei Markgr. and antiplasmodial activity of selected indole alkaloids.

A new indole alkaloid, 12-hydroxy-N-acetyl-21(N)-dehydroplumeran-18-oic acid (13), and 11 known indole alkaloids: 3,4,5,6-tetradehydro-ß-yohimbine (3), 19(E)-hunteracine (4), ß-yohimbine (5), yohimbine (6), 19,20-dehydro-17-α-yohimbine (7), uleine (10), 20-epi-dasycarpidone (11), olivacine (8), 20-epi-N-nor-dasycarpidone (14), N-demethyluleine (15) and 20(E)-nor-subincanadine E (12) and a boonein δ-lactone 9, ursolic acid (1) and 1D,1O-methyl-chiro-inositol (2) were isolated from the EtOH extracts of different parts of Aspidosperma ulei Markgr. (Apocynaceae). Identification and structural elucidation were based on IR, MS, ¹H- and ¹³C-NMR spectral data and comparison to literature data. The antiplasmodial and antimalarial activity of 1, 5, 6, 8, 10 and 15 has been previously evaluated and 1 and 10 have important in vitro and in vivo antimalarial properties according to patent and/or scientific literature. With the aim of discovering new antiplasmodial indole alkaloids, 3, 4, 11, 12 and 13 were evaluated for in vitro inhibition against the multi-drug resistant K1 strain of the human malaria parasite Plasmodium falciparum. IC50 values of 14.0 (39.9), 4.5 (16.7) and 14.5 (54.3) mg/mL (mM) were determined for 3, 11 and 12, respectively. Inhibitory activity of 3, 4, 11, 12 and 13 was evaluated against NIH3T3 murine fibroblasts. None of these compounds exhibited toxicity to fibroblasts (IC50 > 50 mg/mL). Of the five compounds screened for in vitro antiplasmodial activity, only 11 was active.