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The above-ground part of the Salsola passerine was found to contain ~13% (w/w) of polysaccharides extractable with water and aqueous solutions of ammonium oxalate and sodium carbonate. The fractions extracted with aqueous sodium carbonate solutions had the highest yield. The polysaccharides of majority fractions are characterized by similar monosaccharide composition; namely, galacturonic acid and arabinose residues are the principal components of their carbohydrate chains. The present study focused on the determination of antioxidant activity of the extracted polysaccharide fractions and elucidation of the structure of polysaccharides using nuclear magnetic resonance (NMR) spectroscopy. Homogalacturonan (HG), consisting of 1,4-linked residues of α-D-galactopyranosyluronic acid (GalpA), rhamnogalacturonan-I (RG-I), which contains a diglycosyl repeating unit with a strictly alternating sequence of 1,4-linked D-GalpA and 1,2-linked L-rhamnopyranose (Rhap) residues in the backbone, and arabinan, were identified as the structural units of the obtained polysaccharides. HMBC spectra showed that arabinan consisted of alternating regions formed by 3,5-substituted and 1,5-linked arabinofuranose residues, but there was no alternation of these residues in the arabinan structure. Polysaccharide fractions scavenged the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical at 0.2–1.8 mg/mL. The correlation analysis showed that the DPPH scavenging activity of polysaccharide fractions was associated with the content of phenolic compounds (PCs).

The above-ground part of the

Methods were developed for the synthesis of new pyrido[2,3-d]pyrimidine and pyrimidino[4,5-d][1,3]oxazine derivatives. When heated under reflux with MeONa in BuOH, 5-acetyl-4-aminopyrimidines, acylated with carboxylic anhydrides or acid chlorides, are transformed into pyrido[2,3-d]pyrimidin-5-one derivatives, i.e., the acetyl methyl group and the amide carbonyl moiety are involved in the cyclization. In the presence of an activated CH2 group (e.g., PhCH2) in the amide moiety, the cyclization involves this group and the acetyl carbonyl giving rise to pyrido[2,3-d]pyrimidin-7-one derivatives. The reaction of 5-acetyl-4-aminopyrimidines with carboxylic acid chlorides under reflux in xylene followed by addition of a base affords pyrimidino[4,5-d][1,3]oxazines.

A new method for the synthesis of quinazolines based on the annulation of the benzene ring to 5-acetyl-6 methylpyrimidin-2-one(thione) derivatives has been proposed. Condensation of the latter at the methyl group with dimethylformamide dimethyl acetal in boiling PhH leads to the formation of 5-acetyl-6-[2-(dimethylamino)vinyl]pyrimidin-2-ones(thiones), which, when boiled with MeONa in MeOH, cyclize to 5-hydroxyquinazolin-2-ones(thiones). Similarly, 5-acetyl-6-methyl-4-(trifluoromethyl)pyrimidine was converted to 5-hydroxy-4-(trifluoromethyl)quinazoline. Quinazolines are not formed from 5-acetyl-6-methylpyrimidines condensed with dimethylformamide dimethyl acetal at the acetyl group, but 5-acetyl-6-methylpyrimidines can be used to obtain pyrido[2,3-d] pyrimidine derivatives.

An extract from the knotwood of Abies sibirica (Siberian fir) was studied by HPLC, NMR spectroscopy, and mass spectrometry with the goal to identify new sources of phytoestrogens, which are promising medicinal agents, and to obtain new representatives of natural compounds of the indicated group. The following compounds were found in the extract and identified: 2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-4-[1-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)methyl]tetrahydrofuran (1), 5′-(7-hydroxymatairesinyl)-5″-(7‴-hydroxymatairesinol) (2), 2,3-bis(4-hydroxy-3-methoxybenzyl)butane-1,4-diol (3, (−)-secoisolariciresinol), and 3-(4-hydroxy-3-methoxybenzyl)-5-(4-hydroxy-3-methoxyphenyl)-4-(hydroxymethyl)dihydro-furan-2(3H)-one (4). Compound 2 was previously unknown.

Presence of the cell wall glycopolymer rhamnan was established for members of the genus Curtobacterium (family Microbacteriaceae) by using chemical and NMR spectroscopic methods. The rhamnan with the repeating unit, →2)-α-L-Rhap-(1→3)-α-L-Rhap-(1→, was found in C. flaccumfaciens pv. flaccumfaciens VKM Ас-1923T, C. flaccumfaciens pv. poinsettiae VKM Ас-1924T, C. pusillum VKM Ac-2099T, C. herbarum VKM Ac-2512T, and Curtobacterium sp. VKM Ac-1811. Each of the studied strains also contained a second, acidic phosphate-free polysaccharide. NMR spectra of these polysaccharides differed, indicating the structural differences. Cell wall hydrolysates of all studied strains were found to contain rhamnose, mannose, glucose, galactose, and glucosamine. Further research will facilitate more detailed characterization of the composition of cell wall glycopolymers in Curtobacterium species, as well as evaluation of their taxonomic significance. The data on the polymer structure will contribute to understanding of the mechanisms of colonization and infection of higher organisms by Curtobacterium species and bacterial interaction in microbial communities and with abiotic environmental objects.

The kinetics and mechanism of corrosion of an Au anode in a weakly basic aqueous solution of 2,2-dimethyl-1,3-diaminopropane (2,2-DM-1,3-DAP) were studied by gravimetry and cyclic voltammetry. Scanning and transmission electron microscopy was used to determine that under galvanostatic conditions the products of anode corrosion are reduced on a steel cathode with the formation of not only an electrolytic Au deposition on the cathode, but also colloidal gold nanoparticles in the electrolyte medium. The product of the interaction of 2,2-DM-1,3-DAP with atmospheric CO2, namely, the carbamic acid internal salt 3-ammonio-2,2-dimethyl-propylcarbamate, was isolated from the reaction solution.

The reaction of 6-(R-amino)-5-acetyl-4-methylsulfonyl-2-phenylpyrimidines with amines was studied. 6-Arylamino derivatives react with alkylamines to form 6-alkylamino-4-arylamino-5-acetyl-2-phenylpyrimidines, which upon refluxing in benzene with dimethylformamide dimethylacetal are converted to 4-alkylamino-8-aryl-2-phenylpyrido[2,3-d]pyrimidin-5(8H)-ones. The cyclization proceeds selectively with participation of the arylamino group only, the alkylamino group being not involved. At the same time, refluxing of 5-acetyl-4,6-dibenzylamino-2-phenylpyrimidine with dimethylformamide dimethylacetal in toluene affords the product of condensation on the acetyl group, which upon refluxing in o-xylene transforms to 4-benzylamino-8-benzyl-2-phenylpyrido[2,3-d]pyrimidin-5(8H)-one.

The synthesis of a vicinally branched trisaccharide composed of two d-galactofuranoside residues attached viaβ-(1 → 2)- and β-(1 → 3)-linkages to the α-d-galactopyranoside unit has been performed for the first time. The reported trisaccharide represents the galactoxylomannan moiety first described in 2017, which is the capsular polysaccharide of the opportunistic fungal pathogen Cryptococcus neoformans responsible for life-threatening infections in immunocompromised patients. The NMR-data reported here for the synthetic model trisaccharide are in good agreement with the previously assessed structure of galactoxylomannan and are useful for structural analysis of related polysaccharides. The target trisaccharide as well as the constituent disaccharides were analyzed by a combination of computational and NMR methods to demonstrate good convergence of the theoretical and experimental results. The results suggest that the furanoside ring conformation may strongly depend on the aglycon structure. The reported conformational tendencies are important for further analysis of carbohydrate-protein interaction, which is critical for the host response toward C. neoformans infection.

According to HPLC, NMR spectroscopy, and mass spectrometry, the extracts of the knotwood of Salix capreal. contain catechin (1), 7-O-(β-d-glucopyranosyl)dihydrokaempferol (2), 7-O-(β-d-glucopyranosyl)dihydrokaempferol-4′-O-methyl ether (3), 7-O-(β-d-glucopyranosyl)naringenin (prunin) (4), naringenin (5), and dihydrokaempferide (6). Compound 3 was not described previously.

The structures of three cell wall glycopolymers of the phytopathogen Rathayibacter tritici VKM Ac-1603T (family Microbacteriaceae, order Micrococcales, class Actinobacteria) were established by chemical methods and NMR spectroscopy. Polymer 1 is a branched rhamnomannan with the repeating unit →3)-α-[β-D-Xylp-(1→2)]-D-Manp-(1→2)-α-D-Rhap-(1→3)-α-D-Manp-(1→2)-α-D-Rhap-(1→; polymer 2 is a linear rhamnomannan with the repeating unit →2)-α-D-Manp-(1→2)-α-D-Rhap-(1→3)-α-D-Manp-(1→2)-α-D-Rhap-(1→; polymer 3 is a branched teichuronic acid containing monosaccharide residues GlcA, Gal, Man, and Glc at a 1:1:1:5 ratio (see the text for the structures). It has been demonstrated that representatives of four Rathayibacter species studied to date (R. tritici VKM Ac-1603T, R. iranicus VKM Ac-1602T, R. toxicus VKM Ac-1600 and “Rathayibacter tanaceti” VKM Ac-2596) contain differing patterns of phosphate-free glycopolymers. At the same time, the above Rathayibacter strains have a common property — the presence of rhamnomannans with D-rhamnose. These rhamnomannans may be linear or branched and differing in the positions of glycosidic bonds and side substituents. The presence in the cell wall of rhamnomannans with D-rhamnose may serve as useful chemotaxonomic marker of the genus Rathayibacter.

Fucosylated chondroitin sulfate CJ from the body wall of sea cucumber Cucumaria japonica was depolymerized by the treatment with H

The γ-aminobutyric acid type A (GABA

The solvent-free sulfur-mediated reactions of phosphinic chlorides with alkyl diamines were developed for the practical synthesis of unknown phosphoryl-substituted 4,5-dihydro-1H-imidazoles, 1,4,5,6-tetrahydropyrimidines, and thioamides. Their good tolerance to functional groups, broad substrate scope, and easy scalability were shown. The chemoselective preparation of a variety of phosphoryl-substituted bis(thioamides) was accomplished via the adjustment of a solvent.

The studies on the recently discovered pyranoside-into-furanoside rearrangement have led us to conformational investigations of furanosides upon their total sulfation. Experimental NMR data showed that in some cases drastic changes of the ring conformation occurred while sometimes only the conformation of the exocyclic C4–C5 linkage changed. Herein we describe a combined quantum chemical and NMR conformational investigation of three common monosaccharide furanosides as their propyl glycosides: α-mannose, β-glucose and β-galactose. Full exploration of the furanoside ring by means of ab initio calculations was performed and coupling constants were calculated for each of the low-energy conformers. The results demonstrated preferred trans-orientation of H4–H5 protons in the non-sulfated molecules which changed to gauche-orientation upon sulfation. The effect is less pronounced in the galactosides. For all the studied structures changes in the conformational distribution were revealed by quantum mechanical calculations, that explained the observed changes in intraring coupling constants occurring upon introduction of sulfates.

A branched O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Yersinia rohdei H274-36/78 and found to contain d-rhamnose, d-mannose, and 3,6-dideoxy-4-C-[(S)-1-hydroxyethyl]-d-xylo-hexose called yersiniose A (Yer). Partial acid hydrolysis of the O-polysaccharide eliminated Yer residues to give a modified linear polysaccharide. Studies by sugar analysis and 1H and 13C NMR spectroscopy, including computational NMR analysis, enabled structure elucidation of a hexasaccharide repeating unit of the O-polysaccharide having two Yer residues attached as monosaccharide side chains. The O-antigen gene cluster of Y. rohdei H274-36/78 located between JUMPStart and galF genes contained putative genes for synthesis of precursors of two O-antigen constituents, GDP-d-Man and GDP-d-Rha, whereas genes responsible for synthesis of CDP-Yer were within the chromosome outside the O-antigen gene cluster. Glycosyltransferase genes and ABC 2 transporter genes were present in the O-antigen gene cluster, and hence the structure established is consistent with the polysaccharide synthesis gene content of the genome.

Acinetobacter baumannii, a nonfermentative, Gram-negative, aerobic bacterium, is one of the most significant nosocomial pathogens. The pathogenicity of A. baumannii is based on the cooperative action of many factors, one of them being the production of capsular polysaccharides (CPSs) that surround bacterial cells with a thick protective layer., Acinetobacter baumannii is one of the most clinically important nosocomial pathogens. The World Health Organization refers it to its “critical priority” category to develop new strategies for effective therapy. This microorganism is capable of producing structurally diverse capsular polysaccharides (CPSs), which serve as primary receptors for A. baumannii bacteriophages carrying polysaccharide-degrading enzymes. In this study, eight novel bacterial viruses that specifically infect A. baumannii strains belonging to K2/K93, K32, K37, K44, K48, K87, K89, and K116 capsular types were isolated and characterized. The overall genomic architecture demonstrated that these viruses are representatives of the Friunavirus genus of the family Autographiviridae. The linear double-stranded DNA phage genomes of 41,105 to 42,402 bp share high nucleotide sequence identity, except for genes encoding structural depolymerases or tailspikes, which determine the host specificity. Deletion mutants lacking N-terminal domains of tailspike proteins were cloned, expressed, and purified. The structurally defined CPSs of the phage bacterial hosts were cleaved with the specific recombinant depolymerases, and the resultant oligosaccharides that corresponded to monomers or/and dimers of the CPS repeats (K units) were isolated. Structures of the derived oligosaccharides were established by nuclear magnetic resonance spectroscopy and high-resolution electrospray ionization mass spectrometry. The data obtained showed that all depolymerases studied were glycosidases that specifically cleave the A. baumannii CPSs by the hydrolytic mechanism, in most cases, by the linkage between the K units. IMPORTANCE Acinetobacter baumannii, a nonfermentative, Gram-negative, aerobic bacterium, is one of the most significant nosocomial pathogens. The pathogenicity of A. baumannii is based on the cooperative action of many factors, one of them being the production of capsular polysaccharides (CPSs) that surround bacterial cells with a thick protective layer. Polymorphism of the chromosomal capsule loci is responsible for the observed high structural diversity of the CPSs. In this study, we describe eight novel lytic phages which have different tailspike depolymerases (TSDs) determining the interaction of the viruses with corresponding A. baumannii capsular types (K types). Moreover, we elucidate the structures of oligosaccharide products obtained by cleavage of the CPSs by the recombinant depolymerases. We believe that as the TSDs determine phage specificity, the diversity of their structures should be taken into consideration as selection criteria for inclusion of certain phage candidates in the cocktail designed to control A. baumannii with different K types.

An O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide (LPS) of Pseudomonas donghuensis SVBP6, a bacterium with a broad-spectrum antifungal activity in vitro, particularly that against Macrophomina phaseolina. This latter is one of the most virulent and dangerous pathogens of plants, including soybean which is an economically important crop in Argentina today. The OPS was studied by sugar analysis and spectroscopy (1D and 2D 1H and 13C NMR) showing the following trisaccharide repeating unit: →6)-ɑ-D-ManpNAc-(1 → 3)-β- l -Rhap-(1 → 4)-β-D-Glcp-(1→. The crude LPS, the purified LPS and the O-chain were assayed for their antifungal activity against M. phaseolina at 25, 50, 100, and 200 μg plug−1. The results showed that the crude LPS best inhibition was at 200 μg plug−1, able to inhibit the fungus growth by about 45%, while purified LPS and the corresponding OPS, in the same condition, reduced fungus growth by 65%, and 75%, respectively. Furthermore, the purified LPS and OPS significantly reduced the growth of M. phaseolina already at 100 μg plug−1 compared to the crude LPS. The structure of the O-chain is unique among the bacterial LPS and this is the first time that both the antifungal activity of a bacterial LPS and its corresponding O-chain were described.

We report that in birch leaf pectin, rhamnogalacturonan-I (RG-I) and galacturonan (HG) were found as separate polymers rather than domains of a complex macromolecule. RG-I and HG were separated by anion-exchange and size-exclusion chromatography and studied by using NMR spectroscopy. NMR spectra showed that methyl-esterified D-galactosyluronic acid residues were located only in HG. Oligosaccharides of similar structure to the backbone, but without terminal reducing residues in the NMR spectra, were found in RG-I. We hypothesize, these oligosaccharides and RG-I backbone can be covalently bound due to its co-eluted of from DEAE-cellulose and Sepharose CL-4B. This result differs from the classical RG-I model, which assumes that all Rhap and GalpA residues are located only in the RG-I backbone. In the heteronuclear multiple bond correlation (HMBC) and rotating frame Overhauser effect spectroscopy (ROESY) spectra, the correlation peaks confirming the substitution of 2,4-rhamnose residues at O-4 by only single D-galactose residues were identified.

Crude anionic polysaccharides extracted from the Pacific starfish Lysastrosoma anthosticta were separated by anion-exchange chromatography into fractions LA-F1 and LA-F2. The main fraction LA-F1 was solvolytically desulfated giving rise to preparation LA-F1-DS with a structure of dermatan core [→3)-β-d-GalNAc-(1→4)-α-l-IdoA-(1→]n. Reduction of LA-F1 afforded preparation LA-F1-RED composed mainly of the repeating disaccharide units →3)-β-d-GalNAc4R-(1→4)-α-l-Ido2S3S-(1→, where R was SO3- or H. Analysis of the NMR spectra of the parent fraction LA-F1 led to determine the main component as the oversulfated dermatan sulfate LA-Derm bearing sulfate groups at O-2 and O-3 of α-l-iduronic acid, as well as at O-4 of some N-acetyl-d-galactosamine residues. The minor fraction LA-F2 contained a mixture of LA-Derm and heparinoid LA-Hep, the latter being composed of the fragments →4)-α-d-GlcNS3S6S-(1→4)-α-l-IdoA2S3S-(1→ and →4)-α-d-GlcNS3S-(1→4)-α-l-IdoA2S3S-(1→. The presence of 2,3-di-O-sulfated iduronic acid residues is very unusual both for natural dermatan sulfate and heparinoid. Preparations LA-F1, LA-F2 and LA-F1-RED demonstrated significant anticoagulant effect in vitro.

The cell wall of Clavibacter michiganensis subsp. michiganensis VKM Ас-1403Т (family Microbacteriaceae, class Actinobacteria) contains two polysaccharides. The first one is neutral (1 → 6) linked galactofuranan in which every second galactofuranose residue in the main chain substituted at position 3 by side trisaccharide, β-D-GlcpNAc-(1 → 3)-α-L-Rhap-(1 → 2)-α-D-Fucp-(1 →. The second polymer is pyruvylated galactomannan with the repeating unit, →3)-α-D-Galp-(1 → 3)-α-D-[4,6-S-Pyr]-Manp-(1 → 3)-α-D-Manp-(1 →. The cell wall glycopolymer structures were established by chemical and NMR spectroscopic methods. The obtained results provide new data on the cell wall composition of plant pathogenic species of the genus Clavibacter and can promote understanding the molecular mechanisms involved in colonization and infection of plants.

New 3,20-dihydroxy-13α-19-norpregna-1,3,5(10)-trienes were synthesized. The effects of these compounds on breast cancer cells and ERα activation were investigated. The scaffold of compounds containing the six-membered ring D′ annulated at 16α,17α-positions was constructed via the Lewis acid catalyzed Diels-Alder reaction of butadiene with 3-methoxy-13α-19-norpregna-1,3,5(10),16-tetraen-20-one 5 under a pressure of 600 MPa. The hydrogenation of primary cyclohexene adduct 6 followed by the one-pot reduction–demethylation (DIBAH) gave target epimeric 3,20-dihydroxy steroids 8a and 8b. The Corey-Chaykovsky reaction of the same conjugated ketone 5 gave a 16α,17α-methylene-substituted compound. The reaction of the latter with DIBAH yielded 3,20(R,S)-dihydroxy-16α,17α-methyleno-13α-19-norpregna-1,3,5(10)-triene 10. The hydrogenation of the 16,17-double bond of compound 5 produced a mixture of 17α- and 17β-epimeric ketones, reduction–demethylation of which gave 3,20(S)-dihydroxy-13α,17α-19-norpregna-1,3,5(10)-triene 12a and 3,20(R)-dihydroxy-13α,17β-19-norpregna-1,3,5(10)-triene 12b. All compounds were fully characterized by 1D and 2D NMR, HRMS, and X-ray diffraction. All target compounds showed pronounced cytotoxic effect against MCF-7 breast cancer cells and NCI/ADR-RES doxorubicin-resistant cells at micromolar concentrations. The ERα-mediated luciferase reporter gene assay demonstrated that all compounds, except for compound 10, are ERα inhibitors, while cyclopropane compound 10 proved to be an ERα activator. Docking experiments showed that all compounds are well accommodated to LBD ERα but have some differences in the binding mode.

Two fucosylated chondroitin sulfates SC and SH were isolated from the holothurian species Stichopus chloronotus and Stichopus horrens, respectively. The molar ratio of monosaccharides and sulfate (GalNAc:GlcA:Fuc:SO3Na) was suggested as ∼1:1:1:4 for both polysaccharides. Really this theoretical ratio was slightly distorted by the presence of some fucan sulfate in both preparations (about 2% in SH and 10% in SC), which could not be separated probably due to coincidence with the main components in charge density and molecular weight. The 1D and 2D NMR spectroscopic methods were applied for the detailed structural characterization of SC and SH, which were found to have similar structures. The main chain of SC and SH was shown to be composed of the repeating disaccharide units →4)-β- d -GlcA-(1 → 3)-β- d -GalNAc-(1→ sulfated at O-4 or both at O-4 and O-6 of the N-acetyl-galactosaminyl residues. The ratio of mono- and disulfated GalNAc residues was determined as 1:9 for SC and SH. Only one type of branches linked to O-3 of glucuronyl residues, namely fucosyl 2,4-disulfate residues, were found in both polysaccharides. Therefore polysaccharides SC and SH are two new examples of highly regular fucosylated chondroitin sulfates.

The synthesis of model oligosaccharides related to antigenic galactomannans of the dangerous fungal pathogen Aspergillus fumigatus has been performed employing pyranoside-into-furanoside (PIF) rearrangement and controlled O(5) → O(6) benzoyl migration as key synthetic methods. The prepared compounds along with some previously synthesized oligosaccharides were studied by NMR spectroscopy with the full assignment of 1H and 13C signals and the determination of 13C NMR glycosylation effects. The obtained NMR database on 13C NMR chemical shifts for oligosaccharides representing galactomannan fragments forms the basis for further structural analysis of galactomannan related polysaccharides by a non-destructive approach based on the calculation of the 13C NMR spectra of polysaccharides by additive schemes.

The filamentous anoxygenic phototrophic bacterium Oscillochloris trichoides DG-6 has been studied, and it has been shown that there are no lipopolysaccharides on the cell surface. Fatty acids hydroxylated at the C3 position, amino sugars and phosphate-containing compounds characteristic of lipid A have also not been found. The genes encoding for proteins responsible for the synthesis of lipopolysaccharides and the genes for the transport system, usually localized in the outer membrane of Gram-negative bacteria, have not been detected in the genome. The rigid layer of the cell wall contains a peptidoglycan consisting of alanine, glutamine, ornithine and glycine, in the respective ratio 1.8 : 1.5 : 1.0 : 0.6. Thus, the investigated bacterium, Osc. trichoides, is a monoderm. The cell wall also contains a branched α-1,4-d-glucan with a repeating unit consisting of glucose residues linked by α-1→4 bonds (α-1→6 at the branching sites). Such polymers have not previously been reported in phototrophic bacteria.

A new approach to CF3-containing 3,4-dihydroquinazolin-2(1H)-ones based on the condensation of 5-acetyl-6-methyl-1-phenyl-4-trifluoromethylpyrimidin-2(1H)-one with dimethylformamide dimethyl acetal has been suggested.

The cell wall glycopolymer structures of plant-associated strains Clavibacter sp. VKM Ac-1371, Clavibacter sp. VKM Ac-1372 and Clavibacter sp. VKM Ac-1374, members of three putative new species (family Microbacteriaceae, class Actinobacteria) were studied. Each strain was found to contain two glycopolymers, neutral and acidic ones. The main chain of neutral polymer, identical in all three strains, is (1 → 6)-linked β- d -galactofuranan with every second galactofuranose residue substituted at position 2 by side disaccharide, α- d -Manp-(1 → 2)-α- d -Ribf-(1 → . The second, acidic polymer, is pyruvate-containing galactomannan with the repeating unit, →3)-α- d -Galp-(1 → 3)-α- d -[4,6-S-Pyr]-Manp-(1 → 3)-α- d -Manp-(1 → . Reducing mannopyranose residues of the acidic polysaccharides repeating unit from strains VKM Ac-1372 and VKM Ac-1374 bear O-acetyl residues additionally. The cell wall glycopolymer structures were established by chemical and NMR spectroscopic methods with using one- and two-dimensional techniques 1H,1H COSY, TOCSY, ROESY and 1H,13C HSQC, HMBC. The results obtained provide new data on diversity of the bacterial cell wall glycopolymers and may prove valuable for microbial taxonomy and insight into the molecular mechanisms of interactions between bacteria and plants and also of bacterial adaptation to survival in desert systems.