http:\/\/journal.chemistrycentral.com\/content\/6\/1\/37<\/a><\/p>\n

<\/a><\/p>\n

New monocyclic monoterpenoid glycoside from Mentha haplocalyx Briq.<\/p>\n

Gai-Mei Sheet al<\/p>\n

Chemistry Central Journal 2012, 6:37<\/p>\n

doi:10.1186\/1752-153X-6-37<\/p>\n

new monocyclic monoterpenoid glycosides, rel-(1R,2S,3R,4R) p-menthane-1,2,3-triol 3-O-\u03b2-D-glucopyranoside (1) were isolated from aqueous acetone extract of the aerial parts of Mentha haplocalyx Briq..<\/p>\n

On the basis of spectroscopic methods, including 2D-NMR (HMQC, HMBC, 1H-1H COSY and NOESY), the structures of new were determined as rel- (1R,2S,3R,4R) p-menthane-1,2,3-triol 3-O-\u03b2-D-glucopyranoside (1)<\/p>\n

Compound 1 was obtained as a pale amorphous powder. Its HR-ESI-MS displayed quasi-molecular-ion peak [M\u2009+\u2009Na]+ at m\/z 373.1521 ([C16H30O8Na]+), and the EI-MS gave fragment-ion peaks at m\/z 171 [M\u2009+\u20091\u2013162(glucosyl)-H2O]+ and 153 [M\u2009+\u20091\u2013162(glucosyl)-2H2O]+ corresponding to a molecular formula C16H30O8, with the presence of 16 carbon signals in the 13C-NMR spectrum.<\/p>\n

The 1H- and 13C-NMR spectral data displayed the presence of two secondary methyl \u03b4 0.81 (3H, dJ\u2009=\u20097.0\u2009Hz, H-10), 0.92 (3H, dJ\u2009=\u20097.0\u2009Hz, H-9)], a tertiary methyl \u03b4 1.21 (3H, s, H-7)], two methylenes \u03b4 1.37 (2H, dtJ\u2009=\u200911.7, 8.3\u2009Hz, H-5), 1.40 (1H, m, H-6\u03b1) and 1.57 (1H, m, H-6\u03b2)], four methines (two of them was oxygenated) \u03b4 3.82 (1H, dJ\u2009=\u200910.8, 9.2\u2009Hz, H-3), 3.33 (1H, dJ\u2009=\u200910.8\u2009Hz, H-2), 2.31 (1H, m, H-8), and 1.69 (1H, m, H-4)], and an oxygentated quaternary carbon, suggesting that compound 1 was a menthane-type monoterpene with three OH-groups<\/p>\n

Moreover, 1H-1H COSY correlations were observed between H-C(9)\/H-C(8)\/H-C(10), H-C(8)\/H-C(4), and H-C(6)\/H-C(5)\/H-C(4)\/H-C(3)\/H-C(2), that the deduced spin system implied that the three OH-groups were located at C(1), C(2) and C(3) in 1, respectively. In addition, one glucopyranosyl unit \u03b4 (H) 4.33 (1H, dJ\u2009=\u20098.2\u2009Hz, H-(1\u2032)), \u03b4(C) 105.9 (C-1\u2032)] was evident from 1H- and 13C-NMR of 1. The J value (8.2\u2009Hz) of the anomeric proton concluded the \u03b2-configuration of the glucose moiety, suggesting that 1 was a p-menthane-1,2,3-triol glycoside.<\/p>\n

This was further confirmed by the HMBC experiment, in which correlations of the glucosyl H-1\u2032 (\u03b4 4.33) with the C(3) (\u03b4 81.9) were observed. Furthermore, other HMBC correlations confirmed the structure of compound 1. Thus, these 2D-NMR methods deduced compound 1 as p-menthane-1,2,3-triol 2-O\u03b2-D- glucopyranoside. The coupling constants of 10.8\u2009Hz for H-C(3)\/H-C(2), 9.2\u2009Hz for H-C(3)\/H-C(4) for 1 showed that H-C(2), H-C(3) and H-C(4) were axial protons.<\/p>\n

The relative configuration at C(1) was determined from ROESY correlation of \u03b4 1.21 (Me(7)) with H-2 (\u03b4 3.33). It was in good agreement with those of rel-(1R,2S,3R,4R,6S) p-menthane-1,2,3,6-tetrol . Therefore 1 should possess rel-(1R,2S,3R,4R)-configuration.<\/p>\n","protected":false},"excerpt":{"rendered":"

http:\/\/journal.chemistrycentral.com\/content\/6\/1\/37 New monocyclic monoterpenoid glycoside from Mentha haplocalyx Briq. Gai-Mei Sheet al Chemistry Central Journal 2012, 6:37 doi:10.1186\/1752-153X-6-37 new monocyclic monoterpenoid glycosides, rel-(1R,2S,3R,4R) p-menthane-1,2,3-triol 3-O-\u03b2-D-glucopyranoside (1) were isolated from aqueous acetone extract of the aerial parts of Mentha haplocalyx Briq.. On the basis of spectroscopic methods, including 2D-NMR (HMQC, HMBC, 1H-1H COSY and NOESY), the… Continue reading 2D-NMR (HMQC, HMBC, 1H-1H COSY and NOESY), for rel- (1R,2S,3R,4R) p-menthane-1,2,3-triol 3-O-\u03b2-D-glucopyranoside (1)<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[143],"_links":{"self":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts\/184"}],"collection":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/comments?post=184"}],"version-history":[{"count":2,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts\/184\/revisions"}],"predecessor-version":[{"id":186,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts\/184\/revisions\/186"}],"wp:attachment":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/media?parent=184"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/categories?post=184"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/tags?post=184"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}