Mutagenicity and structure-mutagenicity relationships of furoquinolines, naturally occurring alkaloids of the Rutaceae

Microsomal metabolism of dictamnine: identification of metabolites and evaluation of their mutagenicity in Salmonella typhimurium

“…The identity and purity of dictamnine was confirmed by GC-MS analysis. The data were in agreement with the literature (Paulini et al, 1989).…”

Anticholinesterase activity evaluation of alkaloids and coumarin from stems of Conchocarpus fontanesianus

“…HRESIMS showed ion peaks [M+H] + at m/z 200.0688, 230.0814 and 260.0862 corresponding, respectively, to molecular formulas C 12 H 9 NO 2 , C 13 H 11 NO 3 , and C 14 H 13 NO 4 . This information, associated with fragmentation patterns observed in GC-LREIMS and comparison with those described in the literature (Paulini et al, 1989;Inada et al, 2008;Li et al, 2011), allowed the identification of dictamnine (1), γ-fagarine (2) and skimianine (3). Compound 4 showed a ion peak [M+H] + at m/z 236.1011 in the HRESIMS spectrum, corresponding to molecular formula C 16 H 13 NO and a fragmentation pattern characteristic of quinolone alkaloid (Biavatti et al, 2002).…”

1H and13C NMR spectra of 3,8-dimethoxyfuro[3,2-g]coumarin and maculine fromEsenbeckia grandiflora Martius (Rutaceae)

“…The 13 C chemical shifts of both carbons (C-3 and C-4a) have been interchanged erroneously in literature. 6 The 13 C NMR spectrum (Table 2) of coumarin 2 exhibited 13 carbon signals associated to two methoxyl groups (OMe), four sp 2 methine carbons (CH), six quarternary sp 2 carbons and a conjugated carbonyl group. The 1 H NMR spectrum of 2 (Table 2) revealed the presence of two doublets at υ 6.80 ppm (1H, J D 2.2 Hz) and υ 7.67 ppm (1H, J D 2.2 Hz) characteristic of a disubstituted furan ring, two singlets (υ 3.93 and υ 4.29 ppm) associated to methoxyl groups and two singlets at υ 6.90 (1H) and υ 7.25 ppm (1H), the latter ones being characteristic of hydrogens from the aromatic ring.…”

“…These 865 correlations allowed us to correct the attribution of both carbons previously described in the literature. 6 HMBC spectrum analysis allowed unequivocally assigning all the carbon and hydrogen chemical shifts (Table 1). The 3 J coupling between the hydrogen at υ 7.50 ppm with the carbons at υ 143.8 (C-8a) and υ 155.9 (C-4) ppm confirmed the assignment of this hydrogen at position C-5.…”