Synthesis of a fully protected derivative of O-(N-acetyl-alpha-D-neuraminyl)-(2----3)-O-beta-D-galactopyranosyl-(1- ---3)-O- [(N-acetyl-alpha-D-neuraminyl)-(2----6)]-O-(2-acetamido-2-deoxy-alpha- D-galactopyranosyl)-(1----3)-L-serine

N-(Benzyloxycarbonyl)-O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate]-(2----3)-O-(2,4,6-tri-O-acetyl-beta-D - galactopyranosyl)-(1----3)-O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate-(2----6)]-O-(2-acetamido-4-O-acetyl-2- deoxy-alpha-D- galactopyranosyl)-(1----3)-L-serine benzyl ester was synthesized by using O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5- di-deoxy-D-glycero-alpha-D-galacto-2-nonulopyranosyl)onate]- (2----3)-O-(2,4,6- tri-O-acetyl-beta-D-galactopyranosyl)-(1----3)-O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate-(2----6)]-4-O-acetyl-2-azido-2-deoxy-a lpha- and -beta-D-galactopyranosyl trichloroacetimidate as a key glycotetraosyl donor which, upon reaction with N-(benzyloxycarbonyl)-L-serine benzyl ester, afforded a 44% yield of a mixture of the alpha- and beta-glycosides in the ratio of 2:5.     

Triterpenoid glycosides from the bark of Mimosa tenuiflora.

Two new saponins were isolated from Mimosa tenuiflora and their structures established as 3-O-[alpha-L-rhamnopyranosyl(1----2)-beta-D-glucopyranosyl-(1----3]-(alp ha-L- arabinopyranosyl-(1----4]-beta-D-xylopyranosyl-(1----2)]-[beta-D- xylopyranosyl-(1----4)]-beta-D-glucopyranosyl)-28-O-alpha-L-rhamnopyrano syl oleanolic acid and 3-O-[alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranosyl-(1----3]-(al pha- L-arabinopyranosyl-(1----4]beta-D-xylopyranosyl-(1----2)]-[beta-D- xylopyranosyl-(1----4)]-beta-D-glucopyranosyl) oleanolic acid.     

Synthesis of alpha-D-Manp-(1----3)-[beta-D-GlcpNAc-(1----4)]-[alpha-D-Manp+ ++-(1----6)] - beta-D-Manp-(1----4)-beta-D-GlcpNAc-(1----4)-[alpha-L-Fucp- (1----6)]-D- GlcpNAc, a core glycoheptaose of a "bisected" complex-type glycan of glycoproteins

A synthesis of alpha-D-Manp-(1----3)-[beta-D-GlcpNAc-(1----4)]-[alpha-D-Manp++ +-(1----6)]- beta-D-Manp-(1----4)-beta-D-GlcpNAc-(1----4)-[alpha-L-Fucp-( 1----6)]-D- GlcpNAc was achieved by employing benzyl O-(3,4,6-tri-O-benzyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl)-(1--- -4)-O- (2-O-benzyl-beta-D-mannopyranosyl)-(1----4)-O-(3,6-di-O-benzyl-2-deoxy-2 - phthalimido-beta-D-glucopyranosyl)-(1----4)-3-O-benzyl-2-deoxy-6-O-p- methoxyphenyl-2-phthalimido-beta-D-glucopyranoside as a key glycosyl acceptor. Highly stereoselective mannosylation was performed by taking advantage of the 2-O-acetyl group in the mannosyl donors. The alpha-L-fucopyranosyl residue was also stereoselectively introduced by copper(II)-mediated activation of methyl 2,3,4-tri-O-benzyl-1-thio-beta-L-fucopyranoside.     

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.     

Four major saponins from Solidago canadensis.

Four new bisdesmosidic saponins each containing eight carbohydrate units were isolated from Solidago canadensis. GC, GC-MS, FABMS analysis and mainly the use of 2D NMR techniques allowed their identification as bayogeninglycosides (canadensissaponins 1-4) 3-O- [beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl]-28-O-[alpha-L- rhamnopyranosyl-(1----3)-beta-D-xylopyranosyl-(1----4)-[beta-D- xylopyranosyl-(1----3)]-alpha-L-rhamnopyranosyl-(1----2)-[beta-D- apio-D-furanosyl-(1----3)]-beta-D-6-deoxyglucopyranosyl- (1----]-bayogenin; -(1----2)-[beta-D-apio-D-furanosyl-(1----3)]-ara- binopyranosyl-(1----]-bayogenin; -[alpha-L-rhamnopyranosyl-(1----3)]-beta- D-6-deoxyglucopyranosyl-(1----]-bayogenin and - [alpha-L-rhamnopyranosyl- (1----3)]-arabinopyranosyl-(1----]-bayogenin.     

Synthesis of a branched pentasaccharide sequence of "bisected" structure of N-glycoproteins

For the synthesis of the threefold-branched pentasaccharide, O-alpha-D-mannopyranosyl-(1----3)-O-[(2-acetamido-2-deoxy-beta-D- glucopyranosyl)-(1----4)]-O-[alpha-D-mannopyranosyl-(1----6)]-O-beta-D- mannopyranosyl-(1----4)-2-acetamido-2-deoxy-D-glucopyranose (20), which is a part of the structure of the N-glycoproteins, the disaccharide 4-O-(4-O-acetyl-3,6-di-O-allyl-2-O-benzyl-beta-D-mannopyranosyl) -1,6-anhydro-2-azido-3-O-benzyl-2-deoxy-beta-D-glucopyranose was synthesized as a key compound by use of the silver silicate-catalyst procedure. After elimination of the 4-O-acetyl group, a 2-acetamido-2-deoxy-beta-D-glucopyranosyl group was attached according to the phthalimido method. Further elimination of the allyl groups allowed the linkage of two alpha-D-mannopyranosyl groups in the presence of mercury salt. A deblocking sequence consisting of four steps gave 20.     

Synthesis of a mucin-type O-glycosylated amino acid, beta-Gal-(1----3)-[alpha-Neu5Ac-(2----6)]-alpha-GalNAc-(1----3)- Ser

Total synthesis of O-beta-D-galactopyranosyl-(1----3)-O-[(5-acetamido-3,5-dideoxy- D-glycero-alpha-D-galacto-2-nonulopyranosylonic acid)-(2----6)]-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-(1----3 )-L- serine was achieved by use of the key glycosyl donor O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-(1----3)-O- [methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate-(2----6)]-4-O-acetyl-2-azido-2-deoxy-a lpha-D- galactopyranosyl trichloroacetimidate and the key glycosyl acceptor N-(benzyloxycarbonyl)-L- serine benzyl ester in a regiocontrolled way.     

p-Trifluoroacetamidophenyl O-alpha-D-mannopyranosyl-(1----3)-O-[alpha-D-mannopyranosyl- (1----6)]-beta-D-mannopyranoside

p-Nitrophenyl 2-O-benzyl-4,5-O-cyclohexylidene-beta-D-mannopyranoside (4) was condensed with tetra-O-benzoyl-alpha-D-mannopyranosyl bromide. The resulting, protected disaccharide was converted into p-nitrophenyl O-(2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl)-(1----3)-4-O-benzoyl-2-O- benzyl-beta-D-mannopyranoside (8), which was condensed with tetra-O-benzoyl-alpha-D-mannopyranosyl bromide to give p-nitrophenyl O-(2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl)-(1----3)-O -[2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl-(1----6)]-4-O-benzoyl-2-O -benzyl-beta-D-mannopyranoside (9) in 75% yield. Conversion of the p-nitrophenyl group followed by deprotection then yielded the title compound, whose structure was confirmed by 1H- and 13C-n.m.r. spectroscopy.     

Synthesis of a spacer-containing repeating unit of the capsular polysaccharide of Streptococcus pneumoniae type 23F.

The synthesis is reported of 3-aminopropyl 4-O-(4-O-beta-D-glucopyranosyl-2-O-alpha-L-rhamnopyranosyl-beta-D- galactopyranosyl)-beta-L-rhamnopyranoside 3'-(glycer-2-yl sodium phosphate) (25 beta), which represents the repeating unit of the capsular polysaccharide of Streptococcus pneumoniae type 23F (American type 23) [(----4)-beta-D-Glcp-(1----4)-[Glycerol-(2-P----3)] [alpha-L- Rhap-(1----2)]-beta-D-Galp-(1----4)-beta-L-Rhap-(1----)n). 2,4,6-Tri-O-acetyl-3-O-allyl-alpha-D-galactopyranosyl trichloroacetimidate (5) was coupled with ethyl 2,3-di-O-benzyl-1-thio-alpha-L-rhamnopyranoside (6). Deacetylation of the resulting disaccharide derivative, followed by benzylidenation, and condensation with 2,3,4-trio-O-acetyl-alpha-L-rhamnopyranosyl trichloroacetimidate (10) afforded ethyl 4-O-[3-O-allyl-4,6-O-benzylidene-2-O-(2,3,4-trio-O-acetyl- alpha-L-rhamnopyranosyl)-beta-D-galactopyranosyl]-2,3-di-O-benzyl-1-thio - alpha-L-rhamnopyranoside (11). Deacetylation of 11, followed by benzylation, selective benzylidene ring-opening, and coupling with 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl trichloroacetimidate (15) gave ethyl 4-O-[3-O-allyl-6-O-benzyl-4-O-(2,3,4,6- tetra-O-acetyl-beta-D-glucopyranosyl)-2-O-(2,3,4-tri-O-benzyl-alpha-L- rhamnopyranosyl)-beta-D-galactopyranosyl]-2,3-di-O-benzyl-1-thio-alpha-L - rhamnopyranoside (16). Deacetylation of 16 followed by benzylation, deallylation, and acetylation yielded ethyl 4-O-[3-O-acetyl-6-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl-beta-D-glucopy ran osyl)- 2-O-(2,3,4-tri-O-benzyl-alpha-L-rhamnopyranosyl)-beta-D-galactopyranosyl ]-2,3- di-O-benzyl-1-thio-alpha-L-rhamnopyranoside (20). The glycosyl bromide derived from 20, when coupled with 3-benzyloxycarbonylamino-1-propanol, gave the beta-glycoside (21 beta) as the major product. Deacetylation of 21 beta followed by condensation with 1,3-di-O-benzylglycerol 2-(triethylammonium phosphonate) (27), oxidation, and deprotection, afforded 25 beta.     

Jatropham derivatives and steroidal saponins from the bulbs of Lilium hansonii.

Two new jatropham derivatives and three new steroidal saponins were isolated from the fresh bulbs of Lilium hansonii, along with previously known compounds. The structures of the new compounds were elucidated, on the basis of spectroscopic data and chemical evidence, and by comparing them with those of known compounds, as (-)-5-hydroxy-3-methyl-3-pyrrolin-2-one (jatropham) 5-O-beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranoside, (2S*,4R*)-1-(3-methyl-2-oxo-3-pyrrolinyl)-4-methyl-5-oxo-2-pyrr olidinecarboxyli c acid, 26-O-beta-D-glucopyranosyl-(25R)-5 alpha-furostan-3 beta,22 zeta-diol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside, (25R)-5 alpha-spirostan-3 beta,12 alpha-diol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside and (25R)-spirost-5-en-3 beta,12 alpha-diol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside, respectively. The stereostructure of jatropham dimer, the plain structure of which was presented previously, was confirmed by X-ray crystallographic analysis. The inhibitory activity on cyclic AMP phosphodiesterase of the steroidal saponins was evaluated.     

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.     

Synthesis of modified tetrasaccharide sequences of N-glycoproteins

The tetrasaccharides O-alpha-D-mannopyranosyl-(1----3)-O-[alpha-D- mannopyranosyl-(1----6)]-O-(4-deoxy-beta-D-lyxo-hexopyranosyl)-(1- ---4)-2- acetamido-2-deoxy-alpha, beta-D-glycopyranose (22) and O-alpha-D-mannopyranosyl-(1----3)-O-[alpha-D-mannopyranosyl-(1----6)]-O- beta-D-talopyranosyl-(1----4)-2-acetamido-2-deoxy-alpha, beta-D- glucopyranose (37), closely related to the tetrasaccharide core structure of N-glycoproteins, were synthesized. Starting with 1,6-anhydro-2,3-di-O-isopropylidene-beta-D-mannopyranose, the glycosyl donors 3,6-di-O-acetyl-2-O-benzyl-2,4-dideoxy-alpha-D-lyxo- hexopyranosyl bromide (10) and 3,6-di-O-acetyl-2,4-di-O-benzyl-alpha-D-talopyranosyl bromide (30), were obtained in good yield. Coupling of 10 or 30 with 1,6-anhydro-2-azido-3-O-benzyl-beta-D-glucopyranose to give, respectively, the disaccharides 1,6-anhydro-2-azido-3-O-benzyl-2-deoxy-4-O-(3,6-di-O-acetyl-2-O-benzyl-4 -deoxy- beta-D-lyxo-hexopyranosyl)-beta-D-glucopyranose and 1,6-anhydro-2-azido-3-O-benzyl-2-deoxy-4-O-(3,6-di-O-acetyl-2,4-di-O-ben zyl- beta-D-talopyranosyl)-beta-D-glucopyranose was achieved with good selectivity by catalysis with silver silicate. Simultaneous glycosylation of OH-3' and OH-6' of the respective disaccharides with 2-O-acetyl-3,4,6-tri-O-benzyl-alpha-D-mannopyranosyl chloride yielded tetrasaccharide derivatives, which were deblocked into the desired tetrasaccharides 22 and 37.     

Synthesis of trisaccharide methyl glycosides related to fragments of the capsular polysaccharide of Streptococcus pneumoniae type 18C.

The synthesis is reported of methyl 3-O-(4-O-beta-D-galactopyranosyl-alpha-D- glucopyranosyl)-alpha-L-rhamnopyranoside (1), methyl 2-O-alpha-D-glucopyranosyl-4-O-beta-D-glucopyranosyl-beta-D- galactopyranoside (3), methyl 3-O-(4-O-beta-D-galactopyranosyl-alpha-D-glucopyranosyl)-alpha-L- rhamnopyranoside 3"-(sn-glycer-3-yl sodium phosphate) (2), and methyl 2-O-alpha-D-glucopyranosyl-4-O-beta-D- glucopyranosyl-beta-D-galactopyranoside 3-(sn-glycer-3-yl sodium phosphate) (4), which are trisaccharide methyl glycosides related to fragments of the capsular polysaccharide of Streptococcus pneumoniae type 18C ([----4)-beta-D- Glcp-(1----4)-[alpha-D-Glcp-(1----2)]-[Glycerol-(1-P----3)]-beta-D-Galp - (1----4)-alpha-D-Glcp-(1----3)-alpha-L-Rhap-(1----]n). Ethyl 4-O-acetyl-2,3,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside (10) was coupled with benzyl 2,4-di-O-benzyl-alpha-L-rhamnopyranoside (6). Deacetylation of the product, followed by condensation with 2,4,6-tri-O-acetyl-3-O-allyl-alpha-D-galactopyranosyl trichloroacetimidate (18), gave benzyl 2,4-di-O-benzyl-3-O-[2,3,6-tri-O- benzyl-4-O-(2,4,6-tri-O-acetyl-3-O-allyl-beta-D-galactopyranosyl)-alpha- D- glucopyranosyl]-alpha-L-rhamnopyranoside (19). Acetolysis of 19, followed by methylation, deallylation (----22), and further deprotection afforded 1. Condensation of methyl 2,4-di-O-benzyl-3-O-[2,3,6-tri-O-benzyl-4-O-(2,4,6-tri- O-acetyl-beta-D-galactopyranosyl)-alpha-D-glucopyranosyl]-alpha-L- rhamnopyranoside (22) with 1,2-di-O-benzyl-sn-glycerol 3-(triethyl-ammonium phosphonate) (24), followed by oxidation and deprotection, yielded 2. Condensation of ethyl 2,3,4,6-tetra-O-benzyl-1-thio-beta-D-glucopyranoside (27) with methyl 3-O-allyl-4,6-O-benzylidene-beta-D-galactopyranoside (28), selective benzylidene ring-opening of the product, coupling with 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl trichloroacetimidate (31), and deallylation afforded methyl 6-O-benzyl-4-O-(2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl)-2-O- (2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-beta-D-galactopyranoside (33). Deprotection of 33 gave 3, and condensation of 33 with 24, followed by oxidation and deprotection, gave 4.     

Withanolide glycosides from Dunalia australis.

Four new withanolide glycosides, (20R,22R)-O-(3)-[beta-D- xylopyranosyl(1----3), beta-D-xylopyranosyl(1----4)]-beta-D-glucopyranosyl-3 beta,20-dihydroxy-1 alpha-acetoxy-witha-5,24-dienolide, (20R,22R)-O-(3)-[beta-D-xylopyranosyl(1----3), beta-D-glucopyranosyl(1----4)]-beta-D-glucopyranosyl-3 beta,20-dihydroxy-1 alpha-acetoxy-witha-5,24-dienolide, (20R,22R)-O-(3)-[beta-D- glucopyranosyl(1----3), beta-D-glucopyranosyl(1----4)]-beta-D-glucopyranosyl- 3 beta,20-dihydroxy-1 alpha-acetoxy-witha-5,24-dienolide and (20R,22R)-O-(3)-[beta-D-glucopyranosyl(1----3), beta-D- glucopyranosyl(1----4)]-beta-D-glucopyranosyl-3 beta, 12 beta,20-trihydroxy- 1 alpha,acetoxy-witha-5,24-dienolide, named dunawithanines C, D, E and F, respectively, were isolated from Dunalia australis. Their structures were elucidated on the basis of spectral and chemical evidence, especially NMR data of the peracetates.     

Steroidal saponins from the rhizomes of Smilax sieboldii.

Six new steroidal saponins were isolated from the rhizomes of Smilax sieboldii. Their structures were determined by spectroscopic analysis and hydrolysis to be 3 beta-hydroxy-(25R)-5 alpha-spirostan-6-one (laxogenin) 3-O-beta-D-glucopyranosyl-(1----4)-O-[alpha-L-arabinopyranosyl-(1- ---6)]-beta-D-glucopyranoside, laxogenin 3-O-alpha-L-arabinopyranosyl-(1----6)-beta-D-glucopyranoside, 3 beta,27-dihydroxy-(25S)-5 alpha-spirostan-6-one 3-O-beta-D-glucopyranosyl-(1----4)-O-[alpha-L-arabinopyranosyl-(1- ---6)]- beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-3 beta,22 xi,26-trihydroxy-(25R)-5 alpha-furostan-6-one 3-O-alpha-L-arabinopyranosyl-(1----6)-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-3 beta,22 xi,26-trihydroxy-(25R)-5 alpha-furostan-6- one 3-O-beta-D-glucopyranosyl-(1----4)-O-[alpha-L-arabinopyranosyl-(1- ---6)]- beta-D-glucopyranoside and (25R)-5 alpha-spirostan-3 beta-ol (tigogenin) 3-O-beta-D-glucopyranosyl-(1----4)-O-[alpha-L-arabinopyranosyl- (1----6)]-beta-D-glucopyranoside. The inhibition of cAMP phosphodiesterase by the saponins was evaluated.     

Total synthesis of globotriaosyl-E and Z-ceramides and isoglobotriaosyl-E-ceramide

Stereoselective, total synthesis of O-alpha-D-galactopyranosyl-(1----4) -O-beta-D-galactopyranosyl-(1----4)-O-beta-D-glucopyranosyl-(1----1)-N -tetracosanoyl-[2S,3R,4E (and 4Z)]-sphingenine and O-alpha-D -galactopyranosyl-(1----3)-O-beta-D-galactopyranosyl-(1----4)-O-beta-D -glucopyranosyl-(1----1)-N-tetracosanoyl-(2S,3R,4E)-sphin gen ine was achieved by using O-(2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl) -(1----4)-O-(2,3,6-tri-O-acetyl-beta-D-galactopyranosyl)-(1----4)-2,3,6- tri-O-acetyl-alpha-D-glucopyranosyl trichloroacetimidate, O-(2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl) -(1----4)-O-(2,3,6-tri-O-acetyl-beta-D-galactopyranosyl)-(1----4)-2,3,6- tri-O-acetyl-alpha (and beta)-D-glucopyranosyl fluoride, and O-(2,3,4,6-tetra-O-acetyl-alpha-D -galactopyranosyl)-(1----3)-O-(2,3,6-tri-O-acetyl-beta-D-galactopyran osyl)-(1----4)-2,3,6-tri-O-acetyl-alpha-D-glucopyranosyl trichloroacetimidate.     

Unexpected occurrence of the Ca 19-9 tumor marker in normal human seminal plasma

A monoclonal antibody with anti-sialyl-lacto-N-fucopentaose II specificity, originally thought to be a specific tumor marker in pancreas- and gastrointestinal tumors, reacts strongly with fucose-rich glycoproteins from human seminal plasma obtained by phenol/saline extraction. They are presumed to come from the prostatic gland secretion. Because of the specificity of this monoclonal antibody it can be deduced that the sialyl-Lea-sequence: N-acetyl-alpha-neuraminyl-(2----3)-beta-D-galactopyranosyl-(1--- -3)-[alpha-L-fucopyranosyl-(1----4)]-2-acetamido-2-deoxy-beta-D-gluco pyranosyl-(1----3)-D-galactopyranosyl is present on these glycoproteins. This is also supported by our carbohydrate analysis.     

A gamma-pyronyl-triterpenoid saponin from Pisum sativum.

A new triterpenoid saponin was isolated from Pisum sativum and characterized as 3-O-[alpha-L-rhamnopyranosyl-(1----2)-beta-D-galactopyranosyl(1----2)-be ta- D-glucuronopyranosyl(1----)]-22-O-[3'-hydroxy-2'-methyl-5',6'-dihy dro-4'- pyrone(6'----)]-3 beta, 22 beta, 24-trihydroxyolean-12-ene. The name chromosaponin I is proposed. Chromosaponin I yielded soyasaponin I, known as phytochrome inhibitor, during extraction, but the latter was not found in the free form in this plant.     

Synthesis of an octasaccharide fragment of high-mannose-type glycans of glycoproteins.

O-(alpha-D-Mannopyranosyl)-(1----2)-O-(alpha-D-mannopyranosyl)-(1----3)- O- [(alpha-D-mannopyranosyl)-(1----2)-O-(alpha-D-mannopyranosyl)-(1----6)]- O- (alpha-D-mannopyranosyl)-(1----6)-O-(beta-D-mannopyranosyl)-(1----4)-O-( 2- acetamido-2-deoxy-beta-D-glucopyranosyl)-(1----4)-2-acetamido-2-deoxy- glucopyranose, an octasaccharide fragment of high-mannose type glycan of glycoproteins, was synthesized. Crucial glycosylation of trisaccharide intermediate, benzyl O-(2,4-di-O-benzyl-beta-D-mannopyranosyl)-(1----4)-O-(2-acetamido-3,6-di -O- benzyl-2-deoxy-beta-D-glucopyranosyl)-(1----4)-2-acetamido-3,6-di-O-benz yl-2- deoxy-beta-D-glucopyranoside, was successful only with a di-O-acetyltetradeca-O-benzyl-D-mannopentaosyl chloride. The use of the corresponding hexadeca-O-acetyl-D-mannopentaosyl bromide did not give the desired product.     

Synthesis of methyl glycoside derivatives of tri- and penta-saccharides related to the antithrombin III-binding sequence of heparin, employing cellobiose as a key starting-material

Two key synthons for the title pentasaccharide derivative, methyl O-(methyl 2-O-benzoyl-3-O-benzyl-alpha-L-idopyranosyluronate)-(1----4)-6-O-acetyl- 2-azido - 3-O- benzyl-2-deoxy-beta-D-glucopyranoside and O-(methyl 2,3-di-O-benzyl-4-O- chloroacetyl-beta-D-glucopyranosyluronate)-(1----4)-3,6-di-O-acetyl-2-az ido-2- deoxy-alpha-D- glucopyranosyl bromide, were prepared from a common starting material, cellobiose. They were coupled to give a tetrasaccharide derivative that underwent O-dechloroacetylation to the corresponding glycosyl acceptor. Its condensation with the known 6-O-acetyl-2-azido-3,4-di-O-benzyl-2-deoxy-alpha-D-glucopyranosyl bromide afforded a 77% yield of suitably protected pentasaccharide, methyl O-(6-O- acetyl-2-azido-3,4-di-O-benzyl-2-deoxy-alpha-D-glucopyranosyl)-(1----4)- O- (methyl 2,3- di-O-benzyl-beta-D-glucopyranosyluronate)-(1----4)-O-(3,6-di-O-acetyl-2- azido-2 - deoxy-alpha-D-glucopyranosyl)-(1----4)-O-(methyl 2-O-benzoyl-3-O-benzyl-alpha-L- idopyranosyluronate)- (1----4)-6-O-acetyl-2-azido-3-O-benzyl-2-deoxy-beta-D-glucopyranoside. Sequential deprotection and sulfation gave the decasodium salt of methyl O-(2- deoxy-2-sulfamido-6-O-sulfo-alpha-D-glucopyranosyl)-(1----4)-O-(be ta-D- glucopyranosyl-uronic acid)-(1----4)-O-(2-deoxy-2-sulfamido-3,6-di-O-sulfo-alpha-D-gluco pyranosyl)- (1----4)-O-(2-O-sulfo-alpha-L-idopyranosyluronic acid)-(1----4)-2-deoxy-2- sulfamido-6-O- sulfo-beta-D-glucopyranoside (3). In a similar way, the trisaccharide derivative, the hexasodium salt of methyl O-(2-deoxy-2-sulfamido-6-O-sulfo-alpha-D- glucopyranosyl)- (1----4)-O-(beta-D-glucopyranosyluronic acid)-(1----4)-2-deoxy-2-sulfamido-3,6- di-O- sulfo-alpha-D-glucopyranoside (4) was synthesized from methyl O-(6-O-acetyl-2- azido- 3,4-di-O-benzyl-2-deoxy-alpha-D-glucopyranosyl)-(1----4)-O-(methyl 2,3-di-O- benzyl-beta- D-glucopyranosyluronate)-3,6-di-O-acetyl-2-azido-2-deoxy-alpha-D- glucopyranoside. The pentasaccharide 3 binds strongly to antithrombin III with an association constant almost equivalent to that of high-affinity heparin, but the trisaccharide 4 appears not to bind.