Henryk Myszka
University of Gdańsk
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Featured researches published by Henryk Myszka.
Carbohydrate Research | 2003
Henryk Myszka; Dorota Bednarczyk; Maria Najder; Wieslaw Kaca
2-Acetamido-2-deoxy-D-glucose hydrochloride (D-glucosamine hydrochloride) has been used for the preparation of 1,3,4,6-tetra-O-acetyl-2-deoxy-2-trifluoroacetamido-beta- (4) and 2-tetrachlorophthalimido-alpha,beta-D-glucopyranose (6), which have been transformed into the appropriate bromides and the chloride. Both bromo and chloro sugars were used as a glycosyl donors for the glycosylation of diosgenin [(25R)-spirost-5-en-3beta-ol]. These condensations were conducted under mild conditions, using silver triflate as a promoter, and gave diosgenyl glycosides 9 and 12. Each of them was converted into diosgenyl 2-amino-2-deoxy-beta-D-glucopyranoside hydrochloride (11) and N-acylamido derivatives. The structures of all new glycosides were established by 1H and 13C NMR spectroscopy. These diosgenyl glycosides are the first saponins containing the D-glucosamine residue that have been synthesized. These compounds show promising antitumor activities. The synthetic saponins increase the number of apoptotic B cells, in combination with cladribine (2-CdA), that are isolated from chronic lymphotic leukemia (B-CLL) patients.
Carbohydrate Research | 1988
Zygfryd Smiatacz; Henryk Myszka; Zbigniew Ciunik
Abstract 3,4-Di-O-acetyl-2-deoxy-2-nitroso-β- d -arabinopyranosyl chloride reacts with pyrazole in acetonitrile to afford 1-(3,4-di-O-acetyl-2-deoxy-2-hydroxyimino-α- d -erythro- and -β- d -erythro-pentopyranosyl)pyrazole, the configuration and conformation of which were established on the basis of 1H-n.m.r., polarimetric, and crystallographic data.
Journal of Molecular Structure | 1982
Lech Chmurzyński; Zenon Pawlak; Henryk Myszka
Abstract The UV Spectra of pyridinium N-oxide perchlorates were determined in acetonitrile and compared with the spectrum of pyridine N-oxide. The spectrum of pyridine N-oxide perchlorate is entirely different from the spectra of hydride-bis-pyridine N-oxide perchlorate and pyridine N-oxide. The spectrum of hydride-bis-pyridine N-oxide perchlorate/basic salt/ is similar to that of the conjugate base, but it is not a linear combination of the spectra of the protonated and the unprotanated base species.
Carbohydrate Research | 2013
Dorota Bednarczyk; Agata Walczewska; Daria Grzywacz; Artur Sikorski; Beata Liberek; Henryk Myszka
Four differently N-protected 3,4,6-tri-O-acetyl-2-amino-2-deoxy-d-glucopyranosyl chlorides were synthesized and used as glycosyl donors in reactions with diosgenin. The following amine group protections were tested: trifluoroacetyl (TFA), 2,2,2-trichloroethoxycarbonyl (Troc), phthaloyl (Phth), and tetrachlorophthaloyl (TCP). Products of glycosylation were deprotected to yield diosgenyl 2-amino-2-deoxy-β-d-glucopyranoside. The efficiency of the procedures is discussed. Additionally, a single-crystal X-ray diffraction analysis for 3,4,6-tri-O-acetyl-2-deoxy-2-tetrachlorophthalimido-β-d-glucopyranosyl chloride is reported. Orientations of the pyranose substituents as well as the planarity of the acetoxy and phthalimide groups in the crystal lattice are discussed. Structural evidence is presented for a mesomeric effect in both groups. The preference of the cis over trans orientation of the acetoxy group is confirmed in the crystal lattice.
Carbohydrate Research | 2000
Dorota Bednarczyk; Wieslaw Kaca; Henryk Myszka; Lilianna Serwecińska; Zygfryd Smiatacz; Andrzej Zaborowski
Abstract The N -trifluoroacetyl- and N -tetrachlorophthaloyl-protected bromide of d -glucosamine has been used for the first time as a glycosyl donor for the glycosylation of diosgenin [(25 R )-spirost-5-en-3β-ol]. Both 1,3,4,6-tetra- O -acetyl-2-deoxy-2-trifluoroacetamido-β- d -glucopyranoside and 1,3,4,6-tetra- O -acetyl-2-deoxy-2-tetrachlorophthalimido-α,β- d -glucopyranoside were transformed into the appropriate glycosyl bromides. These reacted with diosgenin under mild conditions, using silver triflate as a promoter, and gave the corresponding protected diosgenyl glycosides. Each was deprotected to give diosgenyl 2-amino-2-deoxy-β- d -glucopyranoside hydrochloride. The structures of the new glycosides were established by 1 H NMR spectroscopy.
RSC Advances | 2016
Illia E. Serdiuk; Milena Reszka; Henryk Myszka; Karol Krzymiński; Beata Liberek; Alexander D. Roshal
A novel fluorescent probe, based on the excited-state intramolecular proton transfer (ESIPT) phenomenon, for evaluation of β-glucosidase activity was designed. The synthesis of the probe was optimized. The conditions for the monitoring of enzymatic cleavage of the probe were developed and discussed from the point of view of reaction kinetics and simplicity of the method.
Journal of Carbohydrate Chemistry | 1995
Zygfryd Smiatacz; Iwona Chrzczanowicz; Henryk Myszka; Pawel Dokurno
Abstract Dimeric methyl (3,4-di-O-acetyl-2-deoxy-2-nitroso-α-d-glucopyranosyl chloride)uronate (1) reacts with nucleophiles such as: ethanol, pyrazole, methyl N-tert-butyloxycarbonyl-L-serinate to give corresponding glycosides. The stereospecifity of the glycosidation reaction depends mainly on the employed nucleophile. The configuration and conformation of the obtained glycosides were established on the basis of 1H NMR and polarimetric data, and additionally the structure of 1-(methyl 3,4-di-O-acetyl-2-deoxy-2-(Z)-hydroxyimino-α-d-arabino-hexopyranosyluronate)pyrazole (6), was supported by X-ray diffraction data.
Beilstein Journal of Organic Chemistry | 2015
Agata Walczewska; Daria Grzywacz; Dorota Bednarczyk; Małgorzata Dawgul; Andrzej Nowacki; Wojciech Kamysz; Beata Liberek; Henryk Myszka
Summary Diosgenyl 2-amino-2-deoxy-β-D-glucopyranoside is a synthetic saponin exhibiting attractive pharmacological properties. Different pathways tested by us to obtain this glycoside are summarized here. Moreover, the synthesis of N-alkyl and N,N-dialkyl derivatives of the glucopyranoside is presented. Evaluation of antibacterial and antifungal activities of these derivatives indicates that they have no inhibitory activity against Gram-negative bacteria, whereas many of the tested N-alkyl saponins were found to inhibit the growth of Gram-positive bacteria and human pathogenic fungi.
Journal of Medical Microbiology | 2011
Oscar Cirioni; Henryk Myszka; Małgorzata Dawgul; Roberto Ghiselli; Fiorenza Orlando; Carmela Silvestri; Lucia Brescini; Wojciech Kamysz; Mario Guerrieri; Andrea Giacometti
Surgical site infections are the second most common hospital- and community-acquired Gram-positive infections, with the US Centers for Disease Control and Prevention estimating that about 500 000 surgical site infections occur annually in the USA. The aim of this work was to determine the in vitro activity of the saponin diosgenyl 2-amino-2-deoxy-β-d-glucopyranoside hydrochloride (HSM1) and its bactericidal effect for a large number of Gram-positive cocci, as well as to investigate its in vitro interaction with seven clinically used antibiotics. In vivo, a wound model was established through the panniculus carnosus of BALB/c mice and then inoculated with 5×10(7) c.f.u. Staphylococcus aureus or Enterococcus faecalis. For each bacterial strain, the study included an infected or non-infected group that did not receive any treatment, a group treated with local HSM1, a group treated with intraperitoneal vancomycin, a group treated with intraperitoneal daptomycin and two groups that received HSM1 local treatment plus intraperitoneal vancomycin or daptomycin. All isolates were inhibited by HSM1 at concentrations of 2-32 mg l(-1). Synergy was demonstrated when HSM1 was combined with vancomycin and daptomycin. In in vivo studies, all groups treated with single drugs showed a statistically significant result compared with the control group. The two groups treated with drug combinations showed the highest antimicrobial efficacy. The good in vitro activities and the in vivo efficacy suggest HSM1 as a promising therapeutic candidate in Gram-positive wound infections.
Journal of Carbohydrate Chemistry | 2014
Monika Norkowska; Henryk Myszka; Magdalena Cyman; Daria Grzywacz; Damian Trzybiński; Artur Sikorski; Beata Liberek
2,3,4,6-tetra-O-Acetyl-D-gluconic acid was synthesized and coupled with 1,3,4, 6-tetra-O-acetyl-2-amino-2-deoxy-β-D-glucopyranose and diosgenyl 3,4,6-tri-O-acetyl-2-amino-2-deoxy-β-D-glucopyranoside to afford N-gluconyl derivatives of diosgenyl 2-amino-2-deoxy-D-glucopyranoside using the methods of solution-phase peptide synthesis. Both coupling reactions suffered from acetyl O→N migration, which caused the N-acetyl derivatives to be formed together with the N-(D-gluconyl) derivatives of D-glucosamine. Additionally, single-crystal X-ray diffraction and high-resolution NMR spectral data for 2,3,4,6-tetra-O-acetyl-D-gluconic acid were analyzed to reveal that this acyclic carbohydrate has adopted the 2G− conformation instead of a typical zigzag conformation. The planarity and cis geometry of the acetoxyl groups are demonstrated.