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Twelve chlorinated aromatic glycosides were isolated from Hypoxis aurea by mass spectrometry guided isolation. [Display omitted] • Twelve chlorinated aromatic glycosides were isolated from Hypoxis aurea tubers. • The chlorine containing fractions were detected by using HR-ESI-TOF mass spectrometry. • This study added the typical profile of the secondary metabolites to the genus Hypoxis. High resolution electrospray time-of-flight mass spectrometric analysis was applied as a guiding tool for selection of the chlorine containing fractions by their characteristic clusters of isotopic molecular ion peaks in mass spectra. Twelve target-compounds, chlorinated aromatic glycosides were carried out and identified from the methanolic extract of Hypoxis aurea tubers by chromatographic methods. Hypoxichlorosides A–F (3 , 6 , 9−12) were found to be undescribed compounds. Curculigine A (1), curculigine B (2), curculigine E (4), curculigine J (5), 2,4,6-trichloro-3-methoxy-5-methylphenyl 1- O -β- d -glucopyranosyl-(1→6)-β- d -glucopyranoside (7) and curculigine C (8) were isolated for the first time from this species. The structure determinations were considered based on the spectroscopic evidence including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three new isoquinoline alkaloids were isolated from Stephania pierrei. • Aromatic glycosides are also the main constituents from the tubers of Stephania pierrei. • Phytochemical information on the polar constituents of Stephania pierrei was given. Three new isoquinoline alkaloids, northalifoline 7- O - β -glucopyranoside (1), (R)-isococlaurine 4'- O - β -glucopyranoside (3) and (1 R ,3 S)-1-(4-hydroxybenzyl)-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (4) were isolated from the tubers of Stephania perriei in addition to 12 known compounds. The structure determinations were considered based on the spectroscopic evidence including 1D and 2D NMR and HR-ESI-MS experiments. [ABSTRACT FROM AUTHOR]

• Four new monoterpene alkaloid glycosides were obtained from Nauclea orientalis. • Monoterpene indole alkaloids bearing with a phenylpropanoid unit were isolated. • The rare 3 R -epimer, kanluaengoside B, was found from Nauclea orientalis. Four new monoterpene alkaloid glycosides, kanluaengosides A–D (1 , 2 , 8 , and 9), were isolated from the leaves of Nauclea orientalis. Additionally, the 12 known compounds were identified as (3 S)-pumiloside (3), strictosamide (4), vincosamide (5), 10-hydroxystictosamide (6), 10-hydroxyvincoside lactam (7), paratunamide B (10), paratunamide C (11), vitexin (12), vicenin-2 (13), kaempferol 3- O -rutinoside (14), rutin (15) and eugenyl β-rutinoside (16). Their structures were determined based on the physical data and the spectroscopic evidence including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

• Phenylethanoid and 4-hydroxybenzyl glycosides were isolated from Magnolia figo. • Derivative of (+)-(7 S ,8 S)-guaiacylglycerol was isolated from Magnolia figo. • This study added the typical profile of the secondary metabolites to the genus Magnolia. Three new phenolic glycosides were isolated from the leaves and twigs of Magnolia figo , and identitified to be 3,4-dihydroxy-β-phenylethoxyl- O -[β-D-glucopyranosyl-(1"→2')-α-L-rhamnopyranosyl-(1'"→3')-(4'- O - trans -caffeoyl)-β-D-glucopyranosyl-(1'""→6')]-β-D-glucopyranoside (champikhaekoside, 8), 4-hydroxybenzyl O -β-D-apiofuranosyl-(1"→2')-[β-D-glucopyranosyl-(1'"→3')]-β-D-glucopyranoside (17) and (+)-(7 S ,8 S)-guaiacylglycerol 8-(6'- O -vanilloyl) -O -β-D-glucopyranoside (26). Additionally, 41 known compounds were identified. The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

Three new aromatic rutinosides were isolated from Pandanus tectorius. • Three new aromatic rutinosides were isolated from Pandanus tectorius. • Aromatic compounds are mainly constituents from the aerial roots of Pandanus tectorius. • It was the first time to report the constituents from Pandanus tectorius of Thai origin. Three new aromatic rutinosides, including 2-methoxy-4-methylphenyl 1- O -rutinoside (1), 3,5-dimethoxy-4-hydroxyphenyl 1- O -rutinoside (3) and (S)-2-hydroxy-2-phenylethyl 1- O -rutinoside (6) were isolated from the fresh aerial roots of Pandanus tectorius. Additionally, the 12 known compounds were identified; 2-methoxy-4-hydroxymethylphenyl 1- O -rutinoside, cuneataside D, benzyl rutinoside, 2-phenethyl rutinoside, viridoside, 7,8- threo -7-methoxysyringylglycerol, 7,8- erythro -7-methoxysyringylglycerol, methyl caffeate, 3,5-di- O -caffeoyl-quinic acid 1-methyl ether, 4,5-di- O -caffeoyl-quinic acid 1-methyl ether, 3,4-di- O -caffeoyl- epi -quinic acid methyl ester and hedyotol D 7"- O -β-D-glucopyranoside. The structure determinations were considered based on the physical data and the spectroscopic evidence including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new benzyl triglycoside was isolated from Magnolia sirindhorniae. • (7 R) and (7 S)-Campneoside I were isolated from Magnolia sirindhorniae. • This study added the typical profile of the secondary metabolites to the genus Magnolia. Abstract A new benzyl triglycoside, benzyl O -α- l -rhamnopyranosyl-(1→2)-[β- d -glucopyranosyl-(1→3)]-β- d -glucopyranoside (1) together with two diastereomer phenylethanoid glycosides, (7 R) and (7 S)-campneoside I (10 , 11) were isolated from the leaves of Magnolia sirindhorniae in addition to 20 known compounds. The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

Graphical abstract 2-Aminobenzoyl O -β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside (1) along with wrightiaionosides A (10) and B (11) were isolated from Wrightia antidysenterica. Highlights • 2-Aminobenzoyl diglycoside was isolated from Wrightia antidysenterica. • Two new megastigmane glycosides were obtained from Wrightia antidysenterica. • Benzoxazinoids were obtained from Wrightia antidysenterica of the family Apocynaceae. Abstract A new aminobenzoyl glycoside, 2-aminobenzoyl O -β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside (1) and two new megastigmane glycosides, wrightiaionosides A (10), and B (11), were isolated along with 17 known compounds, including four benzoxazinoid glycosides (2-5), one indole diglycoside (6), three simple aromatic glycosides (7-9), three megastigmane glycosides (12-14), five flavonoid glycosides (15-19) and one lignan (20). The structure elucidation of these compounds was based on analyses of physical and spectroscopical data including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

Graphical abstract A new neolignan and a new monoterpene glycosides were isolated from Magnolia henryi. Highlights • A new neolignan glucoside was isolated from Magnolia henryi. • An unusual (3 R ,6 Z)-9-hydroxylinaloyl 3- O -β- d -glucoside was isolated from Magnolia henryi. • This study added the information data of the secondary metabolites to the genus Magnolia. Abstract A new neolignan glycoside, (7 R ,8 S)-7′-hydroxy-dihydrodehydrodiconiferyl alcohol 9- O -β- d -glucopyranoside (monthaphuoside A, 1) and a new monoterpene glycoside, (3 R ,6 Z)-9-hydroxylinaloyl 3- O -β- d -glucopyranoside (monthaphuoside B, 2), were isolated from the leaves of Magnolia henryi along with (3 R ,6 S)-6,7-dihydroxy-6,7-dihydrolinaloyl 3- O -β- d -glucopyranoside, hodgsonialloside C, syringin, 3,4,5-trimethoxyphenyl-β- d -apiofuranosyl-(1→6)-β- d -glucopyranoside, (+)-syringaresinol O -β- d -glucopyranoside, kaempferol 3- O -neohesperidoside, kaempferol 3- O -α- l -rhamnopyranosyl-(1→2)-[α- l -rhamnopyranosyl-(1→6)]-β- d -glucopyranoside, rutin, quercetin 3- O -α- l -rhamnopyranosyl-(1→2)-[α- l -rhamnopyranosyl-(1→6)]-β- d -glucopyranoside, 3-hydroxy-5,6-epoxy-β-ionol 3- O -β- d -glucopyranoside, (6 S ,9 R)-roseoside, (6 R ,9 R)-3-oxo-α-ionol β- d -glucopyranoside, byzantionoside B, citroside A, and bridelionoside B. The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

Graphical abstract Three new flavonol triglycosides, champaluangosides A–C (1–3), were isolated from Magnolia utilis. Highlights • Three new flavonol triglycoside were isolated from Magnolia utilis. • Phenolic glycosides having allose as a core sugar unit were isolated from Magnolia utilis. • This study added the information data of the secondary metabolites to the genus Magnolia. Abstract Three undescribed flavonol triglycosides, rhamnetin-3- O -α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→6)]-β- d -glucopyranoside (champaluangoside A), rhamnetin-3- O -α- l -rhamnopyranosyl-(1→2)-[α- l -rhamnopyranosyl-(1→6)]-β- d -galactopyranoside (champaluangoside B) and rhamnocitrin-3- O -α- l -rhamnopyranosyl-(1→2)-[α- l -rhamnopyranosyl-(1→6)]-β- d -glucopyranoside (champaluangoside C), were isolated from Magnolia utilis in addition to eleven known compounds; quercetrin-3- O -α- l -rhamnopyranosyl-(1→2)-[α- l -rhamnopyranosyl-(1→6)]-β- d -glucopyranoside, oxytroflavoside G, magnoloside A, magnoloside M, magnoloside D, manglieside A, manglieside B, 1,2-di- O -β- d -glucopyranosyl-4-allylbebzene, syringrin, benzyl β- d -allopyranoside and (+)-syringaresinol- O -β- d -glucopyranoside. The structure elucidation of these compounds was based on analyses of physical and spectroscopic data. [ABSTRACT FROM AUTHOR]

A new monoterpene glucoside, (3 S ,6 S )-6,7-dihydroxy-6,7-dihydrolinaloyl 6- O -β- d -glucopyranoside, along with two new aromatic glycosides, benzyl O -α- l -rhamnopyranosyl-(1 → 2)-β- d -glucopyranoside and 3,4-dihydroxyphenethyl O -α- l -rhamnopyranosyl-(1 → 2)-[α- l -rhamnopyranosyl−(1 → 3)]-β- d -glucopyranoside were isolated from Magnolia thailandica . Additionally, 29 known compounds, (3 S ,6 R )-6,7-dihydroxy-6,7-dihydrolinaloyl 6- O -β- d -glucopyranoside, benzyl O -β- d -glucopyranoside, benzyl O -β- d -apiofuranosyl-(1 → 2)-β- d -glucopyranoside, icariside F 2 , benzyl O -β- d -apiofuranosyl-(1 → 2)-[β- d -glucopyranosyl-(1 → 3)]-β- d -glucopyranoside, vanillic acid β- d -glucopyranosyl ester, 3-​hydroxy-​4,​5-​dimethoxyphenyl-​β-​D-​glucopyranoside, 3,4,5-trimethoxyphenyl-β- d -apiofuranosyl-(1 → 6)-β- d -glucopyranoside, icariside D 2 , 2-hydroxy-5-(2-hydroxyethyl)phenyl β- d -glucopyranoside, decaffeoylverbascoside, verbascoside, isoverbascoside, crassifolioside, isocrassifolioside, echinacoside, 2′-rhamnoechinacoside, syringin, syringinoside, isosyringinoside, icariside E 5 , (+)-pinoresinol-β- d -glucopyranoside, isoeucommin A, (+)-syringaresinol O -β- d -glucopyranoside, kaempferol 3- O -rutinoside, kaempferol 3- O -α- l -rhamnopyranosyl-(1 → 2)-[α- l -rhamnopyranosyl-(1 → 6)]-β- d -glucopyranoside, rutin, (6 S ,9 S )-roseoside, and citroside A were identified. The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

Three new phenylethanoid glycosides, 2-(3-hydroxy-4-methoxyphenyl)ethyl 1- O -β- d -allopyranoside (hodgsonialloside A, 1 ), 2-(3-hydroxy-4-methoxyphenyl)ethyl 1- O -β- d -glucopyranosyl-(1 → 4)-β- d -allopyranoside (hodgsonialloside B, 2 ) and 2-(3-methoxy-4-hydroxyphenyl)ethyl 1- O -β- d -allopyranoside (hodgsonialloside C, 3 ) were isolated from the leaves of Magnolia hodgsonii in addition to six known compounds, tyrosol 4- O -β- d -xylopyranosyl-(1 → 6)-β- d -glucopyranoside ( 4 ), kaempferol 3- O -neohesperidoside ( 5 ), kaempferol 3- O -rutinoside ( 6 ), kaempferol 3- O -α- l -rhamnopyranosyl-(1 → 2)-[α- l -rhamnopyranosyl-(1 → 6)]-β- d -glucopyranoside ( 7 ), (+)-syringaresinol O -β- d -glucopyranoside ( 8 ), and oblongionoside C ( 9 ). The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. [ABSTRACT FROM AUTHOR]

A new furan-2-carbonyl C -(6′- O -galloyl)-β-glucopyranoside (scleropentaside F, 1 ) and a new alkyl glucoside [butane-2,3-diol 2-(6′- O -galloyl)- O -β-glucopyranoside, 2 ] were isolated from the entire hemi-parasitic plant, Dendrophthoe pentandra growing on Tectona grandis together with ten known compounds including, benzyl- O -β- d -glucopyranoside ( 3 ), benzyl- O -α- l -rhamnopyranosyl-(1 → 6)-β- d -glucopyranoside ( 4 ), benzyl- O -β- d -apiofuranosyl-(1 → 6)-β- d -glucopyranoside ( 5 ), methyl gallate 3- O -β- d -glucopyranoside ( 6 ), methyl gallate 3- O -(6′- O -galloyl)-β- d -glucopyranoside ( 7 ), (+)-catechin ( 8 ), procyanidin B-1 ( 9 ) and procyanidin B-3 ( 10 ), bridelionoside A ( 11 ), and kiwiionoside ( 12 ). In addition, compounds 1, 3 – 9 were isolated from this species growing on the different host, Mangifera indica . The structure elucidations were based on physical data and spectroscopic evidence including 1D and 2D experiments. [ABSTRACT FROM AUTHOR]

A new 2-carboxy-dihydrostilbene glucoside, 2-carboxy-3,5,4′-trihydroxydihydrostilbene 3- O -β- d -glucopyranoside ( 1 ) and a new flavan diglycoside, (2 S )-5,7,4′-trihydroxyflavan 7- O -β- d -apiofuranosyl-(1 → 6)- O -β- d -glucopyranoside ( 3 ) were isolated from the aerial portion of Thai origin Desmodium heterocarpon together with five known compounds, lunularic acid 4′- O -β- d -glucopyranoside ( 2 ), vitexin ( 4 ), isovitexin ( 5 ), (−)- epi -catechin 3- O -β- d -glucopyranoside ( 6 ), and (−)- epi -afzelachin 3- O -β- d -glucopyranoside ( 7 ). The structure determinations were based on physical data and spectroscopic evidence including 1D- and 2D-NMR experiments. The presence of 2-carboxy-dihydrostilbene derivatives from this species added the information data of this compound-type to the plant kingdom. [ABSTRACT FROM AUTHOR]

Three new colchicinoid glucosides, dongduengosides A-C were isolated from seedless pods of Thai origin Gloriosa superba together with colchicoside, colchicine, 2-demethylcolchicine and luteolin 7- O -β- d -glucopyranoside. In addition, colchicine, 2-demethylcolchicine, 3-methylcolchicine, colchicoside, epi -catechin and quercetin 3- O -β- d -glucopyranoside were identified from seeds. The structure determinations were based on physical data and spectroscopic evidence including 1D- and 2D-experiments. This study showed that the different part of seedless pods and seeds provided the major difference in compounds. [ABSTRACT FROM AUTHOR]

A new class of secondary metabolites of the family Apocynaceae, benzoxazinoid, was reported for the first time from Wrightia religiosa . A new benzoxazinoid glycoside, (2 S )-2- O -β- d -glucopyranosyl-2 H -1,4-benzoxazin-3(4 H )-one ( 2 ) and a new indole diglycoside, indoxyl 3- O -β- d -apiofuranosyl-(1 → 6)-β- d -glucopyranoside ( 4 ) were isolated, together with twelve known compounds, including benzoxazinoid glycosides ( 1, 3 ), simple aromatic glycosides ( 5 – 8 ), a lignan glycoside ( 9 ), flavonol glycosides ( 10 – 13 ) and a megastigmane glucoside ( 14 ). The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. A benzoxazinoid with (2 S )-configuration was isolated for the first time from natural source. [ABSTRACT FROM AUTHOR]

Three new glucosides of phenylpropanoic acid derivatives (micromelumosides A–C) and a new coumarin glucoside (micromelumoside D) were isolated from the aerial portions of Micromelum minutum in addition to 15 known compounds, 3,4-dihydro-1,2-secomicrominutinin 9- O -β-​ d -glucopyranside, umbelliferone-​7-​ O -​α-​ l -​rhamnopyranosyl-​(1 → 6)​-​β-​ d -​glucopyranoside, scopolin, haploperoside A, ( S )-peucedanol 7- O -β- d -glucopyranoside, ( R )-peucedanol 7- O -β- d -glucopyranoside, decuroside V, 4-hydroxy-2,6-dimethoxyphenyl 4- O -β- d -glucopyranoside, vanilloloside, 3,5-dimethoxybenzyl alcohol 4- O -β- d -glucopyranoside, (+)-lyoniresinol 3α- O -β- d -glucopyranoside, (+)-syringaresinol 4- O -β- d -glucopyranoside, kaempferol 3- O -sophoroside, kaempferol 3- O -rutinoside, and citroside B. The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D and 2D NMR. [ABSTRACT FROM AUTHOR]

An unusual iridoid diglycoside (specioside 6′- O -α- d -galactopyranoside) and a new phenylethanoid triglycoside (heterophragmoside) were isolated from the leaves and branches of Heterophragma sulfureum together with specioside, verminoside, 6- trans -feruloylcatapol, stereospermoside, (−)-lyoniresinol 3α- O -β- d -glucopyranoside, (+)-lyoniresinol 3α- O -β- d -glucopyranoside, (−)-5′-methoxyisolariciresinol 3α- O -β- d -glucopyranoside, (+)-5′-methoxyisolariciresinol 3α- O -β- d -glucopyranoside, and dehydroconiferyl 4- O -β- d -glucopyranoside. The structural elucidations were based on analyses of chemical and spectroscopic data. [ABSTRACT FROM AUTHOR]

Two new 5-methyl ether flavone glucosides (7,4′,5′-trihydroxy-5,3′-dimethoxyflavone 7- O -β-D-glucopyranoside and 7,4′-dihydroxy-5-methoxyflavone 7- O -β-D-glucopyranoside) were isolated from the leaves of Thai mangrove Bruguiera gymnorrhiza together with 7,3′,4′,5′-tetrahydroxy-5-methoxyflavone, 7,4′,5′-trihydroxy-5,3′-dimethoxyflavone, luteolin 5-methyl ether 7- O -β-D-glucopyranoside, 7,4′-dihydroxy-5,3′-dimethoxyflavone 7- O -β-D-glucopyranoside, quercetin 3- O -β-D-glucopyranoside, rutin, kaempferol 3- O -rutinoside, myricetin 3- O -rutinoside and an aryl-tetralin lignan rhamnoside. The structure of a lignan rhamnoside was found to be related to racemiside, an isolated compound from Cotoneaster racemiflora , and also discussed. Structure determinations were based on analyses of physical and spectroscopic data including 1D- and 2D-NMR. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two new flavonol tetraglycosides were isolated from the Mitragyna rotundifolia. [•] Eight known compounds were also reported from the leaves of M. rotundifolia. [•] Flavonol tetraglycosides bearing p-coumaroyl unit in tran- and cis-forms attached to the sugar part was the first report from this genus. [Copyright &y& Elsevier]

Five unprecedented furan-2-carbonyl C-glycosides, scleropentasides A-E, and two phenolic diglycosides, 4-hydroxy-3-methoxybenzyl 4-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside and 2,6-dimethoxy-p-hydroquinone 1-O-β-D-xylopyranosyl-(1→6)-β-d-glucopyranoside, were isolated from leaves and twigs of Scleropyrum pentandrum together with potalioside B, luteolin 6-C-β-D-glucopyranoside (isoorientin), apigenin 8-C-β-D-glucopyranoside (vitexin), apigenin 6,8-di-C-β-D-glucopyranoside (vicenin-2), apigenin 6-C-α-L-arabinopyranosyl-8-C-β-D-glucopyranoside (isoschaftoside), apigenin 6-C-β-D-glucopyranosyl-8-C-β-D-xylopyranoside, adenosine and l-tryptophan. Structure elucidations of these compounds were based on analyses of chemical and spectroscopic data, including 1D and 2D NMR. In addition, the isolated compounds were evaluated for their radical scavenging activities using both DPPH and ORAC assays., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Glycosides of pyrrole alkaloid (pyrrolemarumine 4″-O-α-L-rhamnopyranoside) and 4'-hydroxyphenylethanamide (marumosides A and B) were isolated from leaves of Moringa oleifera along with eight known compounds; niazirin, methyl 4-(α-L-rhamnopyranosyloxy)benzylcarbamate, benzyl β-D-glucopyranoside, benzyl β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside, kaempferol 3-O-β-D-glucopyranoside, quercetin 3-O-β-D-glucopyranoside, adenosine and L-tryptophan. Structure elucidations were based on analyses of chemical and spectroscopic data including 1D- and 2D-NMR., (Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.)

A new 3-hydroxydihydrobenzofuran glucoside, gnaphaliol 9-O-β-D-glucopyranoside (2), was isolated from the aerial parts of Gnaphalium polycaulon together with 1-{(2R*,3S*-3-(β-D-glucopyranosyloxy)-2,3-dihydro-2-[1-(hydroxyl methyl)vinyl]-1-benzofuran-5-yl}-ethanone or gnaphaliol 3-O-β-D-glucopyranoside (1), (Z)-3-hexenyl O-β-D-glucopyranoside (3) and adenosine (4). The absolute configurations at C-2 and C-3 positions of compound 1 were determined to be 2R and 3R. The structures of these compounds were elucidated on the basis of their physical and spectroscopic data.

An efficient and convenient method for the synthesis of 2-deoxy-2-iodo-O-glycosides from tri-O-acetyl-D-glucal with various alcohols by using I₂-Cu(OAc)₂ is described. The 21 examples of corresponding glycosides were obtained in high yields, with good anomeric selectivity., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

An amino acid derivative, L-(-)-(N-trans-cinnamoyl)-arginine, was isolated from the whole plant of Glinus oppositifolius (L.) Aug. DC. along with kaempferol 3-O-galactopyranoside, isorhamnetin 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-galactopyranoside, vitexin, vicenin-2, adenosine and L-phenylalanine. The structure determinations were based on analyses of chemical and spectroscopic methods.