Flavonoids from two Lonchocarpus species of the Yucatan Peninsula

Leaves, stem bark and root of Lonchocarpus xuul and Lonchocarpus yucatanensis were studied separately. A chalcone, 2',4-dimethoxy-6'-hydroxylonchocarpin (), and the flavones 5,4'-dihydroxy-3'-methoxy-(6:7)-2,2-dimethylpyranoflavone (2) and 5,4'-dimethoxy-(6:7)-2,2-dimethylpyrano-flavone (3), together with the known carpachromene (4), were isolated from the leaves of both species. Similarly, the previously reported flavans xuulanin (5) and 3beta-methoxyxuulanin (6), together with the novel 3beta,4beta,5-trimethoxy-4'-hydroxy-(6:7)-2,2-dimethylpyranoflavan (7), 3-hydroxy-4,5-dimethoxy-(6:7)-2,2-dimethyl-pyranoflavan (8), and 3,4-dihydroxy-5-methoxy-(6:7)-2,2-dimethylpyranoflavan (10), were isolated from the stem bark and root of both species. Finally, the known 2',4'-dihydroxy-3'-(3-methylbut-2-enyl) chalcone (13) was obtained from the root of L. xuul only. The structures of the various metabolites were established by interpretation of their spectroscopic data.     

Stemodane and stemarane diterpenoid hydroxylation by Mucor plumbeus and Whetzelinia sclerotiorum

Incubation of stemodin (1) with Mucor plumbeus ATCC 4740 resulted in the formation of 2alpha,6beta,13-trihydroxystemodane (2), 2alpha,3beta,13-trihydroxystemodane (3), 2alpha,11beta,13-trihydroxystemodane (4) and 2alpha,13,14-trihydroxystemodane (5), while stemodinone (7) afforded 6alpha,13-dihydroxystemodan-2-one (8) and 6alpha,12alpha,13-trihydroxystemodan-2-one (9). Metabolites obtained from the bioconversion of stemarin (11) were 8,13,19-trihydroxystemarane (12) and 2alpha,13,19-trihydroxystemarane (13). 19-N,N-Dimethylcarbamoxy-13-hydroxystemarane (14) was not transformed by the fungus. Stemodin (1) was incubated with Whetzelinia sclerotiorum ATCC 18687 to produce 2alpha,7beta,13-trihydroxystemodane (6) and 2alpha,11beta,13-trihydroxystemodane (4). Stemodinone (7) was converted to 7beta,13-dihydroxystemodan-2-one (10). Compounds 2, 4, 9, 10, 12 and 13 have not been previously reported.     

Radiolytic transformation of 2,2',4'-trihydroxychalcone

Radiolysis of 2,2',4'-trihydroxychalcone, a natural antioxidant present in fruit and vegetables, was performed in ethanol in the absence or in the presence of dioxygen. The degradation process of chalcone was followed in de-aerated solution by HPLC, NMR, FAB-LSIMS mass spectroscopy and analytical TLC. Under anaerobic conditions, six new products (three couples of diastereoisomers) were identified. Four of them kept the chalcone skeleton with OCH(2)CH(3), CH(OH)CH(3) and H substitutions on C(alpha) and C(beta). Thus the target was the alpha-beta double bond on which ethanol radicals were added. The two other compounds were formed in a second stage and exhibited a cyclization between the substituent on C(beta) and the carbonyl group. In the presence of dioxygen, these reactions were prevented and chalcone was protected. This study was the first step toward understanding of the behavior chalcone in irradiated fruits and vegetables.     

18-nor-Podocarpanes and podocarpanes from the Bark of Taiwania cryptomerioides

Seven nor- and podocarpane-type diterpenes were isolated from the bark of Taiwania cryptomerioides Hayata, including three 18-nor-podocarpanes: 18-nor-1beta,4alpha,14-trihydroxy-13-methoxy-8,11,13-podocarpatriene (1), 18-nor-1beta,4alpha,13,14-tetrahydroxy-8,11,13-podocarpatrien-7-one (2), 18-nor-1beta,4alpha,14-trihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (3), 1beta,14,19-trihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (4), 1beta,13,14,18-tetrahydroxy-8,11,13-podocarpatrien-7-one (5), 18-acetoxy-1beta,13,14-trihydroxy-8,11,13-podocarpatrien-7-one (6), and 1beta,14,18-trihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (7). Their structures were determined by application of 1D and 2D NMR spectroscopy and other techniques. Podocarpane-type diterpenes do not occur extensively in nature, and the presumed oxidative enzyme in this plant will be of interest to identify.     

Polyhydroxyserratane triterpenoids from Diphasiastrum complanatum

Serratane triterpenoids were identified from Diphasiastrum complanatum (L.) Holub, including serratane-3alpha,14alpha,15alpha,20beta,21beta,24,29-heptol (1), 3alpha,20beta,21beta-trihydroxyserrat-14-en-24-oic acid (2), 3beta,20beta,21beta-trihydroxyserrat-14-en-24-oic acid (3), 3alpha,20beta,21beta-trihydroxy-16-oxoserrat-14-en-24-oic acid (4), and 16-oxolyclanitin-29-yl E-4'-hydroxyl-3'-methoxycinnamate (5) on the basis of their spectroscopic data as well as nine known analogs.     

Kahiricosides II-V, cycloartane glycosides from an Egyptian collection of Astragalus kahiricus

Four cycloartane-type saponins, kahiricosides II-V (1-4), were isolated from the aerial parts of Astragalus kahiricus of Egyptian origin. Their structures were established as 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-beta-D-glucopyranoside, 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-(2'-O-acetyl)-beta-D-glucopyranoside, 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-(6'-O-acetyl)-beta-D-glucopyranoside, and 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-beta-D-glucopyranosyl-27-O-beta-D-glucopyranoside based on chemical and spectral evidences. All compounds exhibited very weak cytotoxicity against the A2780 ovarian cancer cell line.     

Polyhydroxylated steroidal constituents from the fresh rhizomes of Tupistra yunnanensis

Six new polyhydroxylated steroidal saponins, tupistrosides A-F (1-6), together with nine known steroids, were isolated from the fresh rhizomes of Tupistra yunnanensis. Their structures were elucidated to be (25S)-1beta,4beta,5beta-trihydroxy-spirostane-3beta-yl O-alpha-l-arabinopyranoside (1), 1beta,24beta-dihydroxy-spirost-5,25(27)-dien-3alpha-yl O-beta-d-glucopyranoside (2), (22S,25S)-1alpha,2beta,3alpha,5alpha-tetrahydroxy-furo-spirostane-26-yl O-beta-d-glucopyranoside (3), 1beta,3alpha,22 xi-trihydroxy-furost-5,25(27)-dien-26-yl O-beta-d-glucopyranoside (4), 26-O-beta-d-glucopyranosyl-1beta,22-dihydroxy-furost-5-en-3alpha-yl O-beta-d-glucopyranoside (5) and 22-methoxy-1beta,2beta,3beta,4beta,5beta,7alpha-hexahydroxy-furost-25(27)-en-6-one-26-yl O-beta-d-glucopyranoside (6), respectively, by means of spectroscopic analysis and the results of acid hydrolysis.     

Triterpenoid saponins from Pteleopsis suberosa stem bark

Thirteen oleanane saponins (1-13), four of which were new compounds (1-4), were isolated from Pteleopsis suberosa Engl. et Diels stem bark (Combretaceae). Their structures were determined by 1D and 2D NMR spectroscopy and ESI-MS spectrometry. The compounds were identified as 2alpha,3beta,19alpha,23,24-pentahydroxy-11-oxo-olean-12-en-28-oic acid 28-O-beta-D-glucopyranosyl ester (1), 2alpha,3beta,19beta,23,24-pentahydroxy-11-oxo-olean-12-en-28-oic acid 28-O-beta-D-glucopyranosyl ester (2), 2alpha,3beta,19alpha,23-tetrahydroxy-11-oxo-olean-12-en-28-oic acid 28-O-beta-D-glucopyranosyl ester (3), and 2alpha,3beta,6beta,19alpha,24-pentahydroxy-11-oxo-olean-12- en-28-oic acid 28-O-beta-D-glucopyranosyl ester (4). The presence of alpha,beta-unsaturated carbonyl function was not common in the oleanane class and the aglycons of these compounds were not found previously in the literature. Moreover, the isolated compounds were tested against Helicobacter pylori standard and vacA, and cagA clinical virulence genotypes. Results showed that compound 6 has an anti-H. pylori activity against three metronidazole-resistant strains (Ci 1 cagA, Ci 2 vacA, and Ci 3).     

ent-Clerodane diterpenes and other constituents from the liverwort Adelanthus lindenbergianus (Lehm.) Mitt

Eleven ent-clerodanes, 13-hydroxy-cis-ent-cleroda-3,14-diene, 15-hydroxy-cis-ent-cleroda-3,13(E)-diene, 1beta,12:15,16-diepoxy-cis-ent-cleroda-13(16),14-dien-18alpha,6alpha-olide, 8beta,12:15, 16-diepoxy-cis-ent-cleroda-13(16),14-dien-18alpha,6alpha-olide, 1beta,16:15,16-diepoxy-cis-ent-cleroda-12,14-dien-18alpha,6alpha-olide, 7beta,12:8beta,12-diepoxy-15-hydroxy-cis-ent-cleroda-13-en-16,15:18alpha,6alpha-diolide, 7beta,12:8beta,12-diepoxy-16-hydroxy-cis-ent-cleroda-13-en-15,16:18alpha,6alpha-diolide, 1alpha-acetoxy-8beta,12-epoxy-15-hydroxy-cis-ent-cleroda-13-en-16,15:18alpha,6alpha-diolide, 1beta,12-epoxy-16-hydroxy-cis-ent-cleroda-13-en-15,16:18alpha,6alpha-diolide, 8beta,12-epoxy-15-hydroxy-trans-cleroda-13-en-16,15:18alpha,6alpha-diolide, 8beta,12-epoxy-16-hydroxy-trans-cleroda-13-en-15,16:18alpha,6alpha-diolide along with the known clerodane diterpenes anastreptin and orcadensin have been isolated from the liverwort Adelanthus lindenbergianus (Lehm.) Mitt. Furthermore, three eudesmane sesquiterpenes together with the known (-)-1beta,10-epoxyaristolan, 3,4-seco-4(23),20(29)-lupadien-3,28-dicarboxylic acid dimethyl ester and two acetophenone derivatives were identified by spectroscopic methods, essentially MS and NMR experiments.     

Taxanes with C-5-amino-side chains from the needles of Taxus canadensis

Five taxanes with an amino-side chain on C-5 were identified for the first time in the needles of the Canadian yew, Taxus canadensis. Their structures were characterized as 2alpha,7beta,9alpha,10beta,13-pentaacetoxy-11beta-hydroxy-5alpha-(3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),12-diene (1), 2alpha,9alpha-dihydroxy-10beta,13alpha-diacetoxy-5alpha-(3'-methylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (2), 2alpha17-dihydroxy-9alpha,10beta,13alpha-triacetoxy-5alpha-(3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (3), 2alpha-hydroxy-7beta,9alpha,10beta,13alpha-tetraacetoxy-5alpha-(2'-hydroxy-3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (4), and 9alpha-hydroxy-2alpha,10beta,13alpha-triacetoxy-5alpha-(3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (5) on the basis of 1D-, 2D-NMR spectroscopic data and high-resolution fast atom bombardment MS analyses. Metabolite (1) was isolated from the needles of the Canadian yew for the first time but had previously been detected in the stems of the Japanese yew, whereas taxanes (2-5) are only now reported. Metabolite (3) is the first reported nitrogen-containing taxane with a 17-hydroxyl substitution.     

Saponins from Allium minutiflorum with antifungal activity

Three saponins, named minutoside A (1), minutoside B (2), minutoside C (3), and two known sapogenins, alliogenin and neoagigenin, were isolated from the bulbs of Allium minutiflorum Regel. Elucidation of their structure was carried out by comprehensive spectroscopic analyses, including 2D NMR spectroscopy and mass spectrometry. The structures of the new compounds were identified as (25R)-furost-2alpha,3beta,6beta,22alpha,26-pentaol 3-O-[beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranosyl] 26-O-beta-D-glucopyranoside (1), (25S)-spirostan-2alpha,3beta,6beta-triol 3-O-beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranoside (2), and (25R)-furost-2alpha,3beta,5alpha,6beta,22alpha,26-esaol 3-O-[beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranosyl] 26-O-beta-D-glucopyranoside (3). The isolated compounds were evaluated for their antimicrobial activity. All the novel saponins showed a significant antifungal activity depending on their concentration and with the following rank: minutoside B>minutoside C>minutoside A. No appreciable antibacterial activity was recorded. The possible role of these saponins in plant-microbe interactions is discussed.     

Biotransformation of terpenes from Stemodia maritima by Aspergillus niger ATCC 9142.

Incubation of stemodin (1) in cultures of Aspergillus niger ATCC 9142 resulted in the production of 2alpha,3beta,13-trihydroxystemodane (2), 2alpha,7beta,13-trihydroxystemodane (3) and 2alpha,13,16beta-trihydroxystemodane (4), while stemodinone (5) afforded 13,18-dihydroxystemodan-2-one (6) and 13,16beta-dihydroxystemodan-2-one (7). Four novel metabolites were obtained from the bioconversion of stemarin (8) by the fungus, namely 18-hydroxystemaran-19-oic acid (9), 7beta,18-dihydroxystemaran-19-oic acid (10), 7alpha,18,19-trihydroxystemarane (11) and 1beta-hydroxystemaran-19-oic acid (12). 19-N,N-Dimethylcarbamoxy-13-hydroxystemarane (13) was also transformed to afford 19-N,N-dimethylcarbamoxy-13,17xi,18-trihydroxystemarane (14).     

Polyhydroxylated steroids from the soft coral Sinularia dissecta

A repeated silica gel column chromatography followed by HPLC purification on the methanol extract of marine soft coral Sinularia dissecta, resulted in the isolation of fifteen polyhydroxylated steroids (1-15), involving six new C-18 functionalized steroids, 3beta-acetoxy-1alpha,11alpha-dihydroxygorgost-5-en-18-oic acid (1), gorgost-5-en-1alpha,3beta,11alpha,18-tetrol (2), 18-acetoxy-1alpha,3beta,11alpha-trihydroxygorgost-5-ene (3), 24(S)-3beta-acetoxy-1alpha, 11alpha-dihydroxyergost-5-en-18-oic acid (4), 24(S)-ergost-5-en-1alpha,3beta,11alpha,18-tetrol (5), and dissectolide (6). The structures of the new compounds were determined on the basis of extensive spectroscopic data (IR, MS, (1)H and (13)C NMR, HMQC, HMBC, and NOESY) analysis. Compound 6 was found as an unusual sterol bearing a lactone functionality.     

Diterpenes and sesquiterpenes from the bark of Taxus yunnanensis

Two taxane-type diterpenes, 10beta-acetoxy-2alpha,5alpha,7beta,9alpha-tetrahydroxytaxa-4(20),11-dien-13-one and 2alpha-acetoxy-9alpha-benzoyloxy-5alpha,7beta,10beta,15-tetrahydroxy-11(15-->1)- abeotaxa-4(20),11-dien-13-one, and two new drimane-type sesquiterpenes, 1beta-acetoxy-7-drimen-11alpha-ol-12,11-lactone and 1beta-acetoxy-11,12-epoxy-6-drimen-8alpha,11alpha-diol, were isolated from the bark of Taxus yunnanensis together with 35 known taxane-type diterpenes, a known drimane-type sesquiterpene and a known flavanone.     

Oleanane-type triterpenes of Embelia schimperi leaves

An investigation of an ethyl acetate extract of Embelia schimperi leaves has led to the isolation of 10 oleanane-type triterpenes characterized as 3beta,16alpha-di-O-acetyl-13beta, 28-epoxyoleanane (1), 3beta-acetyl-16-oxo-13beta, 28-epoxyoleanane (2), 3beta-acetyl-16alpha-hydroxy-13beta, 28-epoxyoleanane (3), 3beta-acetyl-16alpha-hydroxyoleanane-13beta, 28-olide (4), 3beta-acetyl-28-hydroxy-16-oxo-12-oleanene (5), 3beta, 28-di-O-acetyl-16alpha-hydroxy-12-oleanene (6), 3beta-acetyl-11alpha, 28-dihydroxy-16-oxo-12-oleanene (7), 3beta, 11alpha, 16alpha, 28-tetrahydroxy-12-oleanene (8), 3beta-acetyl-16alpha, 28alpha-dihydroxy-13beta, 28-oxydooleanane (9) and 3beta, 28alpha-dihydroxy-16-oxo-13beta, 28-oxydooleanane (10). The known compounds isolated from the same extract included 3beta, 16alpha-dihydroxy-13beta, 28-epoxyoleanane (protoprimulagenin A) (11), 3beta-hydroxy-16-oxo-13beta, 28-epoxyoxyoleanane (aegicerin) (12), 3, 16-dioxo-13beta, 28-epoxyoleanane (embilionone) (13), 3beta, 28-dihydroxy-16-oxo-12-oleanene (schimperinone) (14), taraxerone (15), taraxerol (16) and stigmasterol (17). Structure elucidations were carried out spectroscopically.     

Regulation on the expression and N-glycosylation of integrins by N-acetylglucosaminyltransferase V

The expressions of integrin alpha5, beta1, and alpha6 were studied in H7721 cells by means of flow cytometric and RT-PCR method after transfected with sense and antisense cDNA of N-acetylglucosaminyltransferase V (GnT-V). The transfected cells were characterized by Northern blot. It was found that the order of expression from high to low was beta1>alpha5>alpha6. Transfection of sense GnT-V up-regulated alpha5 and alpha6, but not beta1 subunit, while antisense GnT-V down-regulated alpha5 and beta1, but not alpha6. The alterations of surface integrin subunits were quite compatible with the changes of their mRNAs. Using enzyme-labeled lectin analysis, it was shown that alpha5 subunit contained only C(2)C(2) biantennary N-glycan, which was not regulated by sense and antisense GnT-V. In contrast, beta1 subunit contained both biantennary and tri-/tetra-antennary N-glycans with GlcNAcbeta1,6Manalpha1,6-branch, and the latter was up- and down-regulated by the sense and antisense GnT-V, respectively. Therefore, the amount of biantennary N-glycans on beta1 subunit, but not the integrin protein, was correlated to the cell adhesion to fibronectin and laminin, which was reduced and elevated in the sense and antisense GnT-V-transfected cells, respectively, as we previously reported.     

ent-Kaurenoic acids from Mikania hirsutissima (Compositae)

Four ent-kaurenoic acid derivatives, 2beta,16alpha,17-trihydroxy-ent-kauran-19-oic acid (1), 3beta,16alpha,17-trihydroxy-ent-kauran-19-oic acid (2), 11alpha,15beta-dihydroxy-7-O-beta-d-glucopyranosyl-ent-kaur-16-en-19-oic acid (3) and 1alpha,15beta-dihydroxy-7-O-beta-d-glucopyranosyl-ent-kaur-16-en-19-oic acid (4), were isolated together with five known compounds, 1,5-dicaffeoyl-quinic acid (5), 2-O-glucosyloxy-4-methoxy-cinnamic acid (6), phenethyl alcohol glucoside (7), phenethyl-1-O-beta-d-apiofuranosyl (1-->2) beta-d-glucopyranoside (sayaendoside) (8) and 3,6-dihydroxy-beta-ion-9-ol (9) from the 50% aqueous acetone extract of the aerial parts of Mikania hirsutissima DC. (Compositae). Compounds 1-9 were tested for their proliferative activity toward peripheral blood mononuclear cells (hPBMC); compounds 1 and 2 showed significant activity (43.8% and 36.7%, at 100 microM, respectively) on the lymphocyte.     

Bioactive sucrose esters from Bidens parviflora

An investigation on Bidens parviflora led to the isolation of three sucrose esters and a substituted truxillate. Their structures were elucidated as (6-O-(E)-p-coumaroyl)-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside, (6-O-(E)-p-coumaroyl)-beta-D-fructofuranosyl-(2-->1)-(6-O-(E)-p-coumaroyl)-alpha-D-glucopyranoside II, 6,6'-sucrose ester of (1alpha,2alpha,3beta,4beta)-3,4-bis(4-hydroxyphenyl)-1,2-cyclobutanedicarboxylic acid, dimethyl ester of (1alpha,2alpha,3alpha,4alpha)-2,4-bis(3,4-dihydroxyphenyl)-1,3-cyclobutanedicarboxylic acid on the basis of spectral and chemical evidence. These compounds were subjected to the following bioassays: the histamine release inhibition of rat mast cells induced by antigen-antibody reaction and the inhibitory activity of PGE(2) production by macrophages.     

Steroidal glycosides from the underground parts of Helleborus caucasicus

Four polyhydroxylated and polyunsaturated furostanol glycosides (1-4), named caucasicosides A (1), B (2), C (3) and D (4), were isolated from the MeOH extract of the underground parts of Helleborus caucasicus, along with four spirostanol derivatives, a furostanol glycoside, a furospirostanol glycoside, 20-hydroxyecdysone and the bufadienolides hellebrigenin and deglucohellebrin. The structures of 1-4 were elucidated as furosta-5,20(22),25(27)-triene-1beta,3beta,11alpha,26-tetrol 26-O-beta-D-glucopyranoside (1), 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1beta,3beta,11alpha,26-tetrol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (2), 26-O-beta-d-glucopyranosyl-22alpha-methoxyfurosta-5,25(27)-diene-1beta,3beta,11alpha,26-tetrol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (3), 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1beta,3beta,26-triol 3-O-beta-D-xylopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-4-O-sulfo-alpha-L-arabinopyranoside (4). Structure elucidation was accomplished through the extensive use of 1D- and 2D NMR experiments including 1H-1H (COSY, 1D-TOCSY) and 1H-13C (HSQC, HMBC) spectroscopy along with ESI-MS and HR-ESI-MS. The aglycones of 1-4 have never been reported before.     

Oligosaccharide structure of a functional unit RvH1-b of Rapana venosa hemocyanin using HPLC/electrospray ionization mass spectrometry

In the present study the structures of two glycopeptides (G1 and G1'), isolated from FU RvH(1)-b and two glycopeptides (G2 and G3), isolated from the structural subunit RvH(1) of Rapana venosa hemocyanin, were determined. To structurally characterize the site-specific carbohydrate heterogeneity and binding site of the N-linked glycopeptide(s), a combination of capillary reversed-phase chromatography and ion trap mass spectrometry was used. The amino acid sequences of glycopeptides G1 and G1' determined by Edman degradation and MS/MS sequencing demonstrated that the oligosaccharides are linked to N-glycosylation sites. Two peptides (a glycosylated (G1) and non-glycosylated one) were identified in this fraction and no linkage sites were observed in the latter one. Based on the sequencing of the glycosylated fractions G1, G1', G2 and G3, the carbohydrate structure Man(alpha1-6)Man(alpha1-3)Man(beta1-4)GlcNAc(beta1-4)[Fuc(alpha1-6)]GlcNAc-R could be identified for glycopeptides G1 and G3, and only the typical core structure Man(alpha1-6)Man(alpha1-3)Man(beta1-4)GlcNAc(beta1-4)GlcNAc-R was found for G1' and G2. The Fuc residue found in glycopeptides G1 and G3 is attached to N-acetyl-glucosamine of the carbohydrate core, as often found in other glycoproteins.