Triterpene saponins from Verbascum songaricum.

Songarosaponin A, B and C isolated from the aerial parts of Verbascum songaricum were shown to be 3-O-[alpha-L-rhamnopyranosyl-(1----4)-beta-D-glucopyranosyl-(1----3)]-[b eta-D-glucopyranosyl-(1----2)-beta-D-fucopyranosyl]-olea-11,13-die ne-3 beta-23,28-triol, 3-0-[alpha-L-rhamnopyranosyl-(1----4)-beta-D-glucopyranosyl-(1----3)]-[b eta-D-glucopyranosyl-(1----2)]-beta-D-fucopyranosyl]-olea-1 1-ene-3 beta-13,23,28-tetrol and 3-O-[beta-D-glucopyranosyl-(1----4)]-[beta-D-glucopyranosyl-(1----3)]-[b eta-D-glucopyranosyl-(1----2)]-beta-D-fucopyranosyl]-13 beta,28-epoxyolea-11-ene-3 beta,23-diol.     

Phlinosides A, B and C, three phenylpropanoid glycosides from Phlomis linearis.

Three new phenylpropanoid glycosides, phlinosides A, B and C were isolated from a methanolic extract of the aerial parts of Phlomis linearis. On the basis of chemical and spectral evidence their structures were determined as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-glucopyranosyl-(1----2)-a lpha-L- rhamnopyranosyl-(1----3)-4-O-caffeoyl-beta-D-glucopyranoside, 3,4 dihydroxy-beta-phenylethoxy-O-beta-D-xylopyranosyl-(1----2)-alpha- L- rhamnopyranosyl-(1----3)-4-O-caffeoyl-beta-D-glucopyranoside and 3,4-dihydroxy-beta-phenylethoxy-O-alpha-L-rhamnopyranosyl-(1----2) -alpha- L-rhamnopyranosyl-(1----3)-4-O-caffeoyl-beta-D-glucopyranoside, respectively.     

Nine phenethyl alcohol glycosides from Stachys sieboldii.

Three new phenethyl alcohol glycosides together with six known compounds have been isolated from the leaves of Stachys sieboldii. On the basis of chemical and spectral analyses, the structures of three new compounds named stachysosides A, B and C have been established as 2-(3,4-dihydroxyphenyl)ethyl O-alpha-L-arabinopyranosyl-(1----2)-alpha-L-rhamnopyranosyl- (1----3)-4-O-E-caffeoyl-beta-D-glucopyranoside, 2-(3,4-dihydroxyphenyl)ethyl O-alpha-L-arabinopyranosyl-(1----2)-alpha-L-rhamnopyranosyl- (1----3)-4-O-E-feruloyl-beta-D-glucopyranoside and 2-(3-hydroxy-4-methoxyphenyl)ethyl O-alpha-L-arabinopyranosyl-(1----2)-alpha-L-rhamnopyranosyl- (1----3)-4-O-E- feruloyl-beta-D-glucopyranoside, respectively.     

12-Keto steroidal glycosides from the caudex of Yucca gloriosa.

Eight new steroidal glycosides, tentatively named YS-VI, -VII, -VIII, -IX, -X, -XI, -XII and -XIII were isolated from the caudex of Yucca gloriosa along with P-1, YG-2 and YG-3 previously obtained from flowers. The structures of five of these compounds were elucidated as mexogenin 3-O-beta-D-glucopyranosyl-(1----2)-beta-D-galactopyranoside (YS-VI), gloriogenin 3-O-beta-D-glucopyranosyl-(1----2)-[beta- D-glucopyranosyl-(1----3)]-beta-D-glucopyranoside (YS-VII) and 3-O-beta-D-glucopyranosyl-(1----2)-[beta-D-glucopyranosyl)-(1----3)]- beta-D-galactopyranoside (YS-VIII), manogenin 3-O-beta-lycotetraoside (YS-IX) and 3-O-alpha-L-rhamnopyranosyl-beta-lycotetraoside (YS-X), respectively, on the basis of chemical and spectral evidence.     

Structural elucidation of two capsular polysaccharides from one strain of Bacteroides fragilis using high-resolution NMR spectroscopy.

The capsule of Bacteroides fragilis is unusual in that it consists of two distinct capsular polysaccharides. Using a combination of high-resolution NMR spectroscopy, theoretical calculations, and as few chemical procedures as required, the structure of both polysaccharide antigens (polysaccharides A and B) was elucidated. Using the above procedures, it was possible to obtain the complete structures using minimal quantities of polysaccharides A and B (8 and 5 mg, respectively). Only small amounts of each subjected to chemical analysis were not recoverable. Polysaccharide A is composed of the following repeating unit: [----3)alpha-D-AATp(1----4)[beta-D-Galf(1----3)]alpha-D- GalpNAc(1----3)beta-D-Galp(1----], where AAT is 2-acetamido-4-amino-2,4,6-trideoxygalactose. A pyruvate substituent having the R configuration spans O-4 and O-6 of the beta-D-galactopyranosyl residue. Polysaccharide B is composed of the following repeating unit: [----4)alpha-L-QuipNAc(1----3)beta-D-QuipNAc(1----4)[alpha-L - Fucp(1----2)beta-D-GalpA(1----3)beta-D-GlcpNAc(1----3)]alpha -D-Galp(1----]. A 2-aminoethylphosphonate substituent is situated on O-4 of the N-acetyl-beta-D-glucopyranosyl residue.     

Steroidal glycosides from Agave cantala.

Two new steroidal glycosides, agaveside A and B, isolated from the fruits of Agave cantala were characterized as 3 beta-O-[beta-D-xylopyranosyl-(1----2),beta-D-xylopyranosyl-(1----3), beta-D-glucopyranosyl-(1----3)-[beta-D-xylopyranosyl-(1----3)-beta-D- galactopyranosyl-(1----2)]-beta-D-glucopyranosyl]-(25R)-5 alpha-spirostane and 3 beta-O-[beta-D-xylopyranosyl-(1----2), beta-D-xylopyranosyl-(1----3)-beta-D-glucopyranosyl-(1----3)- [beta-D-galactopyranosyl-(1----2)]-beta-D-glucopyranosyl]-(25R)-5 alpha-spirostane. The structures were elucidated by a combination of 13CNMR spectroscopy, chemical degradation and fast atom bombardment mass spectrometry.     

Structural determination of D-mannans of pathogenic yeasts Candida stellatoidea type I strains: TIMM 0310 and ATCC 11006 compared to IFO 1397

The structures of the cell-wall D-mannans of pathogenic yeasts of Candida stellatoidea Type I strains, IFO 1397, TIMM 0310, and ATCC 11006, were investigated by mild acid and, alkaline hydrolysis, by digestion with the Arthrobacter GJM-1 strain exo-alpha-D-mannosidase, and by acetolysis. The modified D-mannans and their degradation products were studied by 1H- and 13C-n.m.r. analyses. D-Manno-oligosaccharides released by acid treatment from the parent D-mannans were identified as the homologous beta-(1----2)-linked D-manno-oligosaccharides from biose to hexaose, whereas those obtained by alkaline degradation were the homologous alpha-(1----2)-linked D-mannobiose and D-mannotriose. The acid- and alkali-modified D-mannans lacking 1H-n.m.r. signals above 4.900 p.p.m. [corresponding to beta-(1----2)-linked D-mannopyranose units] were acetolyzed with 10:10:1 (v/v) Ac2O-AcOH-H2SO4, and the resultant D-manno-oligosaccharides were also analyzed. It was found that the longest branches of these D-mannans, corresponding to hexaosyl residues, had the following structures: alpha-D-Manp-(1----3)-alpha-D-Manp-(1----2)-alpha-D-Manp+ ++-(1----2)-alpha-D-Manp- (1----2)-alpha-D-Manp-(1----2)-D-Man and alpha-D-Manp-(1----2)-alpha-D-Manp-(1----3)-alpha-D-Manp+ ++-(1----2)-alpha-D-Manp- (1----2)-alpha-D-Manp-(1----2)-D-Man. These results indicate that the D-mannans of C. stellatoidea Type I strains possess structures in common with the D-mannans of Candida albicans serotype B strain (see ref. 4) containing phosphate-bound beta-(1----2)-linked oligo-D-mannosyl residues.     

Two flavonol glycosides, hexandrasides C and D, from the underground parts of Vancouveria hexandra.

In addition to four known glycosides, icariin, epimedin B, epimedosides A and E, two new glycosides of a flavonol with a gamma,gamma-dimethylallyl group were isolated from the underground parts of Vancouveria hexandra. The structures were determined to be des-O-methyl-anhydroicaritin 3-O-beta-D-xylopyranosyl(1----2)-alpha-L-rhamnopyranoside 7-O-beta-D-glucopyranosyl(1----2)-beta-D-glucopyranoside and anhydroicaritin 3-O-alpha-L-rhamnopyranosyl(1----3)-alpha-L-rhamnopyranoside 7-O-beta-D-glucopyranoside by means of spectral analysis.     

Ionone,iridoid and phenylethanoid glycosides from Ajuga salicifolia

From the aerial parts of Ajuga salicifolia (L.) Schreber, a new ionone glycoside (3beta-hydroxy-7,8-dihydro-4-oxo-beta-ionol-9-O-beta-D-glucopyranoside) was isolated, along with the known compounds, corchoionoside C, 8-O-acetylmioporoside, ajugol, harpagide, 8-O-acetylharpagide, lavandulifolioside and leonosides A and B. This is the first report of the occurrence of ionone glycosides and 8-O-acetylmioporoside in Ajuga species. Ajugol, lavandulifolioside, leonoside A and B were isolated for the first time from Ajuga salicifolia. The structures were elucidated by means of 1D-, 2D-NMR spectroscopy, and HR-MALDI mass spectrometry.     

Synthesis of a trisaccharide of 3-deoxy-D-manno-2-octulopyranosylonic acid (KDO) residues related to the genus-specific lipopolysaccharide epitope of Chlamydia

The disaccharides, O-(sodium 3-deoxy-alpha- and -beta-D-manno-2-octulopyranosylonate)-(2----8)-sodium (allyl 3-deoxy-alpha-D-manno-2-octulopyranosid)onate, were prepared via glycosylation of methyl (allyl 4,5,7-tri-O-acetyl-3-deoxy-alpha-D-manno-2-octulopyranosid)onat e with methyl (4,5,7,8-tetra-O-acetyl-3-deoxy-D-manno-2-octulopyranosyl bromide)onate under Helferich and Koenigs-Knorr conditions, respectively. Based on g.l.c.-m.s. data of the alpha- and beta-(2----8)-linked disaccharide derivatives, obtained after carbonyl- and carboxyl-group reduction, followed by methylation, the alpha-anomeric configuration was assigned to the terminal KDO-residue in the KDO-region of Chlamydial lipopolysaccharide. The trisaccharide O-(sodium 3-deoxy-alpha-D-manno-2-octulopyranosylonate)-(2----8)-(sodium 3-deoxy-alpha-D-manno-2-octulopyranosylonate)-(2----4)-sodium (allyl 3-deoxy-alpha-D-manno-2-octulopyranosid)onate was obtained via block synthesis using an alpha-(2----8)-linked disaccharide bromide derivative as the glycosyl donor. Copolymerization of the allyl glycosides with acrylamide gave water-soluble macromolecular antigens, suitable for defining epitope specificities of monoclonal antibodies directed against Chlamydial LPS.     

Primary structure determination of five sialylated oligosaccharides derived from bronchial mucus glycoproteins of patients suffering from cystic fibrosis. The occurrence of the NeuAc alpha(2----3)Gal beta(1----4)[Fuc alpha(1----3)] GlcNAc beta(1----.) structural element revealed by 500-MHz 1H NMR spectroscopy

The structure of sialylated carbohydrate units of bronchial mucins obtained from cystic fibrosis patients was investigated by 500-MHz 1H NMR spectroscopy in conjunction with sugar analysis. After subjecting the mucins to alkaline borohydride degradation, sialylated oligosaccharide-alditols were isolated by anion-exchange chromatography and fractionated by high performance liquid chromatography. Five compounds could be obtained in a rather pure state; their structures were established as the following: A-1, NeuAc alpha(2----3)Gal beta(1----4) [Fuc alpha(1----3)]GlcNAc beta(1----3)Gal-NAc-ol; A-2, NeuAc alpha(2----3)Gal beta(1----4)GlcNAc beta(1----6)-[GlcNAc beta (1----3)]GalNAc-o1; A-3, NeuAc alpha(2----3)Gal beta-(1----4)[Fuc alpha(1----3)]GlcNAc beta(1----3)Gal beta(1----3) GalNAc-o1; A-4, NeuAc alpha(2----3)Gal beta(1----4)[Fuc alpha(1----3)]Glc-NAc NAc beta(1----6)[GlcNAc beta(1----3)]GalNAc-o1; A-6,NeuAc alpha-(2----3) Gal beta(1----4)[Fuc alpha(1----3)]GlcNAc beta(1----6)[Gal beta-(1----4) GlcNAc beta(1----3)]GalNAc-o1. The simultaneous presence of sialic acid in alpha(2----3)-linkage to Gal and fucose in alpha(1----3)-linkage to GlcNAc of the same N-acetyllactosamine unit could be adequately proved by high resolution 1H NMR spectroscopy. This sequence constitutes a novel structural element for mucins.     

Substrate specificities of exo- and endo-type cellulases in the hydrolysis of beta-(1----3)- and beta-(1----4)-mixed D-glucans

An exo-type cellulase (Ex-1) was extracted from Irpex lacteus (Polyporus tulipiferae) and purified essentially to homogeneity. This cellulase attacked cellulosic substrates in an exo-wise fashion to produce almost exclusively cellobiose. In contrast, Ex-1 was found to attack beta-glucans having beta-(1----3)- and beta-(1----4)-mixed linkages in a way similar to an endo-type cellulase. The products formed from barley glucan by Ex-1 were 3(2)-O-beta-D-cellobiosyl-cellobiose much greater than 3(2)-O-beta-D-glucosyl-cellobiose greater than cellobiose much greater than or equal to cellotriose much greater than glucose in the early stage, but no laminaribiose was produced. An endo-type cellulase (En-1) obtained from the same fungus also hydrolyzed beta-glucans but in a typical endo-wise fashion and the products from barley glucan were 3(2)-O-beta-D-glucosyl-cellobiose much greater than 3(2)-O-beta-D-cellobiosyl-cellobiose greater than cellobiose much greater than laminaribiose; no glucose or cellotriose was produced. Thus, it seems likely that En-1 can attack any intramolecular linkage of beta-glucan, while Ex-1 requires the presence of at least cellobiosyl residues adjacent to a beta-(1----3)-D-linked glucosyl residue. This finding, together with the mode of hydrolysis of cellulosic substrates by Ex-1, suggests that the stereochemical structure of successive beta-(1----4)-cellobiosyl residues inserted by beta-(1----3)-D-glucosidic linkage is permissible in the action of Ex-1, although this enzyme prefers the beta-(1----4)-linked cellobiosyl sequence.     

Studies on the active site of Taka-amylase A: its action on phenyl maltooligosides with a charge at their non-reducing-ends

Five modified moltooligosaccharides, phenyl O-6-amino-6-deoxy-alpha-D- glucopyranosyl- (1----4)-O-alpha-D-glucopyranosyl-(1----4)-O-alpha-D-glucopyranosyl-(1-- --4)- alpha-D-glucopyransoide (AG4P), phenyl O-(alpha-D-glucopyranosyluronic acid)-(1----4)-O-alpha-D-glucopyranosyl-(1----4)-O-alpha-d-glucopyran osy l- (1----4)-alpha-D-glucopyranoside (CG4P), phenyl O-6-amino-6-deoxy-alpha-D-glucopyranosyl-(1----4)-O-alpha-D-glucopyra nos yl- (1----4)-O-alpha-D-glucopyranosyl-(1----4)-O-alpha-D-glucopyranosyl-(1-- --4)- alpha-D-glucopyranoside (AG5P), phenyl O-(alpha-D-glucopyranosyluronic acid)-(1----4)-O-alpha-D-glucopyranosyl- (1----4)-O-alpha-D-glucopyranosyl-(1----4)-O-alpha-D-glucopyranosyl-(1-- --4)- alpha-D-glucopyranoside (CG5P), and phenyl O-6-deoxy-6-[(2-pyridyl)amino]-alpha-D-glucopyranosyl-(1----4)- O-alpha-D-glucopyranosyl-(1----4)-O-alpha-D-glucopyranosyl-(1----4)-a lph a-D- glucopyranoside (FG4P), were prepared to examine the active site of Taka-amylase A (TAA) [EC 3.2.1.1, Aspergillus oryzae]. Phenyl alpha-maltotetraoside (G4P) was predominantly hydrolyzed by TAA to maltose and phenyl alpha-maltoside (G2P). While G2P, phenyl alpha-glucoside (GP), and phenol were liberated from AG4P in the ratio of 7:63:30. G4P, phenyl alpha-maltotrioside (G3P), G2P, and GP were liberated from G5P in the ratio of 1:20:73:6, but AG5P was almost completely hydrolyzed to modified maltotriose and G2P. On the hydrolysis of CG4P and CG5P, no remarkable change was observed except for a decrease in the relative reaction rates compared with G4P and G5P, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Phlinosides D and E, phenylpropanoid glycosides, and iridoids from Phlomis linearis.

Two new phenylpropanoid glycosides, phlinosides D and E were isolated from the methanolic extract of the aerial parts of Phlomis linearis, along with the known iridoid glucosides, lamiide, ipolamiide and auroside (= 5-hydroxy-8-epiloganin). On the basis of chemical and spectral evidence the structures of phlinosides D and E were determined as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-xylopyranosyl-(1----2)-al pha-L-rhamnopyranosyl-(1----3)-4-O-feruloyl-beta-D-glucopyranoside and 3,4-dihydroxy-beta-phenylethoxy-O-alpha-L-rhamnopyranosyl-(1----2) -alpha-L- rhamnopyranosyl-(1----3)-4-O-feruloyl-beta-D-glucopyranoside, respectively.     

12-Hydroxy steroidal glycosides from the caudex of Yucca gloriosa.

The structures of the new steroidal saponins (tentatively named YS-XI, -XII and -XIII) have been isolated from the caudex of Yucca gloriosa and characterized as 3-O-beta-D-glucopyranosyl-(1----2)-beta-D-galactopyranosyl 5 beta- (25R)-spirostan-3 beta, 12 beta-diol, 3-O-beta-D-glucopyranosyl-(1----2)- [beta-D-glucopyranosyl-(1----3)]-beta-D-glucopyranosyl 5 beta- (25R)-spirostan-3 beta, 12 beta-diol and 3-O-beta-D-glucopyranosyl-(1----2)- beta-D-galactopyranosyl 5 beta-(25R)-spirostan-2 beta,3 beta,12 beta-triol, respectively.     

N-acetyl-beta-D-glucosaminyltransferases related to the synthesis of mucin-type glycoproteins in human ovarian tissue

The presence of N-acetyl-beta-D-glucosaminyltransferases in microsome preparations from human ovarian tissues was investigated with UDP-GlcNAc and several synthetic oligosaccharides as acceptors. The products were identified by paper chromatography and the linkage of the 2-acetamido-2-deoxy-beta-D-glucopyranosyl group incorporated into oligosaccharides was determined by exoglycosidase digestions, 1H-n.m.r. spectroscopy, and methylation analysis. These results showed that ovarian microsome preparations contain both beta-(1----3)- and beta-(1----6)-N-acetyl-D-glucosaminyltransferase activities which might be involved in the synthesis of mucin-type glycoproteins. Substrate competition tests suggested that both UDP-GlcNAc:-Bn glycoside of beta-D-GlcpNAc-(1----6)-alpha-D-GalpNAc [GlcNAc to GalNAc] and -Bn glycoside of beta-D-Galp-(1----3)-[beta-D-GlcNAc-(1----6)]-alpha-D-GalpNAc [GlcNAc to Gal] beta-(1----3)-N-acetyl-D-glucosaminyltransferase activities reside in a single enzyme species.     

Steroidal glycosides from the bulbs of Lilium dauricum.

The bulbs of Lilium dauricum yielded 11 compounds, including six new steroidal glycosides. The structures have been determined by spectral analysis and hydrolysis to be (25R,26R)-26-methoxyspirost-5-en-3 beta-ol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[alpha-L-arabinopyranosyl-( 1----3)]- beta-D-glucopyranoside, (25R,26R)-26-methoxyspirost-5-en-3 beta-ol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside, (25R)-spirost-5-en-3 beta-ol (diosgenin) 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[alpha-L-arabinopyranosyl- (1----3)]-beta-D-glucopyranoside, (25R)-3 beta,17 alpha-dihydroxy-5 alpha-spirostan-6-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranoside, (25R)-3 beta, 17 alpha-dihydroxy-5 alpha-spirostan-6-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[alpha-L- arabinopyranosyl-(1----3)]-beta-D-glucopyranoside and (20R,22R)-3 beta,20,22-trihydroxy-5 alpha-cholestan-6-one (tenuifoliol) 3-O-alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranoside. The absolute configurations of C-20 and C-22 of tenuifoliol were further confirmed by detailed analysis of the NOE difference spectrum of the corresponding isopropylidene derivative. Several known compounds were also isolated and identified.     

Binding studies on internal immunodeterminants: synthesis of beta-(1----6)-linked oligosaccharide methyl glycosides having one to four internal D-galactopyranosyl residues flanked by gentiobiose residues.

The oligosaccharide glycosides beta-D-Glcp-(1----6)-beta-D-Glcp-(1----6)-[beta-D-Galp-(1----6)]n-beta-D - Glcp-(1----6)-beta-D-Glcp-1----OMe (n = 1-4) were prepared by a convergent block synthesis. Haloacetyl, tert-butyldiphenylsilyl, and dimethylthexylsilyl groups were used as temporary protective groups for the preparation of the intermediate glycosyl donors and acceptors. The deoxygenated trisaccharide glycosides beta-D-Glcp-(1----6)-beta-D-Galp-(1----6)-4-deoxy-beta-D-xylo-Hexp -1----OMe and beta-D-Glcp-(1----6)-4-deoxy-beta-D-xylo-Hexp-(1----6)-beta-D-Galp -1----OMe were also synthesized. The binding of each glycoside to the monoclonal antigalactan antibody IgA J539 was studied and the results support the previous finding that J539 can bind to internal antigenic epitopes. The data are consistent with the interpretation that subsite C of that antibody binds glucose with a Ka of approximately 6 (cf. 10.9 for galactose).     

Biologically active labdane-type diterpene glycosides from the root-stalks of Gleichenia japonica.

A glycoside showing a strong growth inhibition of lettuce was isolated from the root-stalks of Gleichenia japonica and its structure was established to be the 3-O-alpha-rhamnopyranosyl-(1----2)-beta-glucopyranoside of 13-O-alpha-rhamnopyranosyl-(+)-3 beta-hydroxymanool. In addition, two related glycosides were also isolated and they were characterized as the 3-O-beta-fucopyranosyl-(1----3)-alpha-rhamnopyranosyl-(1----2)-beta- glucopyranoside of 13-O-alpha-rhamnopyranosyl-(+)-3 beta-hydroxymanool and the 13-O-rhamnopyranoside of the same diterpene alcohol. The diterpene alcohol accelerated the growth of lettuce.     

Y and blood group B type 2 glycolipid antigens accumulate in a human gastric carcinoma cell line as detected by monoclonal antibody. Isolation and characterization by mass spectrometry and NMR spectroscopy

A monoclonal antibody (mAb), BR55-2, was generated from mice immunized with MCF-7 human breast carcinoma cells. This mAb specifically detected glycolipids with the Y determinant Fuc alpha 1----2Gal beta 1----4GlcNAc(3----1 alpha Fuc)-beta 1----3Gal beta 1----4Glc beta 1----1 Cer and the Y-related B-active difucosylated determinant Gal alpha 1----3Gal(2----1 alpha Fuc) beta 1----4GlcNAc(3----1 alpha Fuc) beta 1----3Gal beta 1----4Glc beta 1----1 Cer, but was not reactive with related monofucosylated glycolipids of type 2 chain (X-antigen, blood group H), type 1 chain (Lea antigen, blood group H and B) or with difucosylated type 2 and type 1 chain structures (A blood group antigen or blood group B and Leb, respectively). A series of glycolipids with Y and blood group B type 2 determinants were detected in human gastric adenocarcinoma cell line KATO III with mAb BR55-2 and with a previously characterized anti-blood group B mAb PA83-52 (Hansson, G. C., Karlsson, K.-A., Larson, G., McKibbin, J. M., Blaszczyk, M., Herlyn, M., Steplewski, Z., and Koprowski, H. (1983) J. Biol. Chem. 258, 4091-4097). The isolated antigens were structurally characterized by mass spectrometry of permethylated and permethylated-reduced derivatives and by proton NMR spectroscopy. In a chromatogram binding assay, mAb BR55-2 and mAb PA83-52 detected minor components with slower mobility than the Y-6 and blood group B-7-type 2 structures. The detection of a B type 2 determinant is the first chemical evidence for the presence of an autologous difucosyl blood group B type 2 antigen in human adenocarcinoma cells.