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The photoinitiated thiol-ene addition reaction is a highly stereo- and regioselective, and environmentally friendly reaction proceeding under mild conditions, hence it is ideally suited for the synthesis of carbohydrate mimetics. A comprehensive study on UV-light-induced reactions of 2,3-unsaturated O-, C-, S- and N-glycosides with various thiols was performed. The effect of experimental parameters and structural variations of the alkenes and thiols on the efficacy and regio- and stereoselectivity of the reactions was systematically studied and optimized. The type of anomeric heteroatom was found to profoundly affect the reactivity of 2,3-unsaturated sugars in the thiol-ene couplings. Hydrothiolation of 2,3-dideoxy O-glycosyl enosides efficiently produced the axially C2-S-substituted addition products with high to complete regioselectivity. Moderate efficacy and varying regio- and stereoselectivity were observed with 2,3-unsaturated N-glycosides and no addition occurred onto the endocyclic double bond of C-glycosides. Upon hydrothiolation of 2,3-unsaturated S-glycosides, the addition of thiyl radicals was followed by elimination of the thiyl aglycone resulting in 3-S-substituted glycals., (©2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Nowadays, the sorbates are the third largest group of antimicrobial preservatives in food and pharmaceutical industries, following the parabens and benzoates whose safety is questioned by recent publications. A disadvantage of sorbates is their pH dependence, as their antimicrobial effect is greatly reduced in alkaline environment. The main, widely used sorbate derivatives are sorbic acid and potassium sorbate, no sorbic acid esters are involved in current industrial application. We aimed to test whether the esters of sorbic acid are capable to extend the antimicrobial spectrum of the original molecule while maintaining its advantageous biocompatibility profile. A comparative biocompatibility study of different derivatives (sorbic acid, potassium sorbate, isopropyl sorbate and ethyl sorbate) was carried out. In vitro cell viability assays of MTT (2-(4,5-dimethyl-2-thiazolyl)-3,5-diphenyl-2H-tetrazolium bromide), Neutral Red (3-amino-7-dimethylamino-2-methylphenazine hydrochloride) and flow cytometry with propidium iodide and annexin were performed on Caco-2 cells. In case of in vivo toxicity study, G. mellonella larvae were injected with different concentrations of the test compounds. Time-kill tests were executed on reference strains of C. albicans, E. coli, and S. aureus. According to the MTT-assay, the IC 50 values were the following: ethyl sorbate, sorbic acid <0.045% w / w , isopropyl sorbate 0.32% w / w , potassium sorbate >0.75% w / w , while Neutral Red values were >0.75% w / w for the esters and potassium sorbate and 0.66% w / w for sorbic acid. Flow cytometry results indicated the higher cell damage in case of isopropyl sorbate. However, the cytotoxic results of isopropyl sorbate, in vivo toxicity study on G. mellonella larvae did not show significant mortality. It was found, that the antimicrobial properties of isopropyl sorbate were outstanding compared to sorbic acid and potassium sorbate. These results indicate, that the use of sorbate esters can be advantageous, hence, further toxicity studies are needed to prove their safety., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

A comprehensive optimization and mechanistic study on the photoinduced hydrothiolation of different d- and l- hexo- and pentoglycals with various thiols was performed, at the temperature range of RT to -120 °C. Addition of thiols onto 2-substituted hexoglycals proceeded with complete 1,2-cis-α-stereoselectivity in all cases. Hydrothiolation of 2-substituted pentoglycals resulted in mixtures of 1,2-cis-α- and -β-thioglycosides of varying ratio depending on the configuration of the reactants. Hydrothiolation of unsubstituted glycals at -80 °C proceeded with excellent yields and, except for galactal, provided the axially C2-S-linked isomers with high selectivity. Cooling was always beneficial to the efficacy, increased the yields and in most cases significantly raised the stereoselectivity. The suggested mechanism explains the different conformational preferences of the intermediate carbon-centered radicals, which is a crucial factor in the stereoselectivity of the reactions., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Herein 1 H and 13 C NMR spectra of ERJ-500, a new hybrid aspirin derivative, covalently conjugated to nitrogen monoxide donor linsidomine are presented as well as NMR spectra of its synthetic intermediate compounds. HPLC-MS measurements data are also included, demonstrating the stability of the linsidomine-aspirin hybrid in oxidation reactions. This data article also concerns miscellaneous myocardial parameters of isolated rat hearts as a complementation of the tables shown in the paper entitled "A new, vasoactive hybrid aspirin containing nitrogen monoxide-releasing molsidomine moiety" Szoke et al., 2019. Column tables represent data of aorta flow, aortic pressure, derivated aortic pressure and cardiac output.

A small library of 3'-deoxy-C3'-substituted xylofuranosyl-pyrimidine nucleoside analogues were prepared by photoinduced thiol-ene addition of various thiols, including normal and branched alkyl-, 2-hydroxyethyl, benzyl-, and sugar thiols, to 3'-exomethylene derivatives of 2',5'-di- O - tert -butyldimethylsilyl-protected ribothymidine and uridine. The bioactivity of these derivatives was studied on tumorous SCC (mouse squamous carcinoma cell) and immortalized control HaCaT (human keratinocyte) cell lines. Several alkyl-substituted analogues elicited promising cytostatic activity in low micromolar concentrations with a slight selectivity toward tumor cells. Near-infrared live-cell imaging revealed SCC tumor cell-specific mitotic blockade via genotoxicity of analogue 10 , bearing an n -butyl side chain. This analogue essentially affects the chromatin structure of SCC tumor cells, inducing a condensed nuclear material and micronuclei as also supported by fluorescent microscopy. The results highlight that thiol-ene chemistry represents an efficient strategy to discover novel nucleoside analogues with non-natural sugar structures as anticancer agents.

Ischemic heart conditions are among the main causes of sudden cardiac death worldwide. One of the strategies for avoiding myocardial infarction is the low-dose, prophylactic use of acetylsalicylic acid (ASA), an inhibitor of platelet aggregation. To avoid the gastrointestinal damage, ASA prodrugs bearing nitric oxide (NO)-donating moiety covalently conjugated to ASA have been synthesized and evaluated extensively worldwide. Herein the synthesis of a new hybrid ASA ester covalently attached to the NO donor linsidomine, an active metabolite of molsidomine (MOL) is reported. Cell viability assay and hemolysis tests were performed in H9c2 cells and rat erythrocytes, respectively. Our new compound, the ERJ-500 not affected negatively the viability of living cells in the concentration range of 100 nM to 100 μM. Using the ex vivo Langendorff method on hearts originated from female rats, compound ERJ-500 displayed a dose-dependent, outwashable vasodilative effect in coronary arteries. Vasodilation was observed on isolated working heart model as well, with elevated stroke volume in hearts treated with ERJ-500. Furthermore, a decreased infarct size was also noticed in ERJ-500 treated hearts after ischemia/reperfusion. Based on these observations it can be expected that our new hybrid ASA may contribute to new pharmacological tool in the therapy of ischemic heart conditions and associated syndromes., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Six series of semisynthetic lipophilic glycopeptide antibiotic derivatives were evaluated for in vitro activity against influenza A and B viruses. The new teicoplanin pseudoaglycon-derived lipoglycopeptides were prepared by coupling one or two side chains to the N-terminus of the glycopeptide core, using various conjugation methods. Three series of derivatives bearing two lipophilic groups were synthesized by attaching bis-alkylthio maleimides directly or through linkers of different lengths to the glycopeptide. Access to the fourth and fifth series of compounds was achieved by click chemistry, introducing single alkyl/aryl chains directly or through a tetraethylene glycol linker to the same position. A sixth group of semisynthetic derivatives was obtained by sulfonylation of the N-terminus. Of the 42 lipophilic teicoplanin pseudoaglycon derivatives tested, about half showed broad activity against influenza A and B viruses, with some of them having reasonable or no cytotoxicity. Minor differences in the side chain length as well as lipophilicity appeared to have significant impact on antiviral activity and cytotoxicity. Several lipoglycopeptides were also found to be active against human coronavirus., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

The photoinitiated thiol-ene coupling reactions of 2-substituted glycals were studied as a generally applicable strategy for stereoselective 1,2-cis-α-thioconjugation. Although all glycals reacted with full α-selectivity, the efficacy of the reactions varied in a broad range depending on their configuration and glycals bearing axial acetoxy substituents reacted with very low efficacy at room temperature. The study revealed that the reaction progress could be promoted by cooling and inhibited by heating. At -80 °C, the equilibrium of the rapidly reversible addition of the thiyl radical to alkenes is shifted almost completely toward products, leading to efficient addition reactions. By exploiting this unique temperature effect a series of α-thio-l-fucosides, -d-galactosides, and d-GlcNAc derivatives were prepared with high efficacy and complete stereoselectivity., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel type of nucleoside analogue in which the sugar part is replaced by a new tricycle, 3,7,10-trioxa-11-azatricyclo[5.3.1.0 5,11 ]undecane has been prepared by substrate-controlled asymmetric synthesis. 1,5-Dialdehydes obtained from properly protected or unprotected uridine, ribothymidine, cytidine, inosine, adenosine and guanosine by metaperiodate oxidation reacted readily with tris(hydroxymethyl)aminomethane to provide the corresponding tricyclic derivatives with three new stereogenic centers. Through a double cyclisation cascade process the tricyclic compounds were obtained in good to high yields, with very high diastereoselectivity. Formation of one stereoisomer, out of the eight possible, was observed in all cases. The absolute configuration of the new stereotriad-containing tricyclic systems was aided by conventional NMR experiments followed by chemical shift calculations using an X-ray crystal structure as reference that was in good agreement with H-H distances obtained from a new ROESY NMR method. The synthesis was compatible with silyl, trityl and dimethoxytrityl protecting groups. A new reagent mixture containing ZnCl 2 , Et 3 SiH and hexafluoroisopropanol was developed for detritylation of the acid-sensitive tricyclano nucleosides.

Sugar-modified nucleosides are prime synthetic targets in anticancer and antiviral drug development. Radical mediated thiol-ene coupling was applied for the first time on nucleoside enofuranoside derivatives to produce a broad range of thio-substituted d-ribo, -arabino, -xylo and l-lyxo configured pyrimidine nucleosides. In contrast to the analogous reactions of simple sugar exomethylenes, surprisingly, hydrothiolation of nucleoside alkenes under the standard conditions of various initiation methods showed low to moderate yields and very low stereoselectivity. Optimizing the reaction conditions, we have found that cooling the reaction mixture has a significant beneficial effect on both the conversion and the stereoselectivity, and UV-light initiated hydrothiolation of C2'-, C3'- and C4'-exomethylene derivatives of nucleosides at -80 °C proceeded in good to high yields, and, in most cases, in excellent diastereoselectivity. Beyond the temperature, the solvent, the protecting groups on nucleosides and, in some cases, the configuration of the thiols also affected the stereochemical outcome of the additions. The anomalous l-lyxo diastereoselectivity observed upon the addition of 1-thio-β-d-gluco- and galactopyranose derivatives onto C4',5'-unsaturated uridines is attributed to steric mismatch between the d-ribo C4'-radical intermediates and the β-configured 1-thiosugars.

A new reagent system consisting of a Lewis acid such as BF3·Et2O or Cu(OTf)2, the mild protic acid hexafluoroisopropanol and the reducing quenching agent triethylsilane was elaborated for O-, N- and S-detritylation of nucleoside, carbohydrate and amino acid derivatives. The method is compatible with acetyl, silyl, acetal and Fmoc groups.

Bis-alkylthio maleimido derivatives have been prepared from teicoplanin pseudoaglycon by reaction of its primary amino group with N-ethoxycarbonyl bis-alkylthiomaleimides. Some of the new derivatives displayed excellent antibacterial activity against resistant bacteria.

Despite the close structural similarity between the heptapeptide cores of the glycopeptide antibiotics teicoplanin and ristocetin, synthetically modified derivatives of their aglycons show significantly different antibacterial and antiviral properties. The teicoplanin aglycon derivatives with one exception proved to be potent antibacterials but they did not exhibit anti-influenza virus activity. In contrast, the aglycoristocetin derivatives generally showed high anti-influenza virus activity and possessed moderate antibacterial activity. A systematic structure-activity relationship study has been carried out on ristocetin and teicoplanin aglycon derivatives, to explore which structural differences are responsible for these markedly different biological activities. According to electronic circular dichroism and in silico conformational studies, it was found that the differences in anti-influenza virus activity are mainly determined by the conformation of the heptapeptide core of the antibiotics controlled by the presence or absence of chloro substituents. Knowledge of the bioactive conformation will help to design new analogs with improved anti-influenza virus activity. For the teicoplanin derivatives, it was shown that derivatization to improve the antiviral efficacy was accompanied by a significant decrease in antibacterial activity., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

In order to obtain new, cluster-forming antibiotic compounds, teicoplanin pseudoaglycone derivatives containing two lipophilic n-octyl chains have been synthesized. The compounds proved to be poor antibacterials, but, surprisingly, they exhibited potent anti-influenza virus activity against influenza A strains. This antiviral action was related to inhibition of the binding interaction between the virus and the host cell. Related analogs bearing methyl substituents in lieu of the octyl chains, displayed no anti-influenza virus activity. Hence, an interaction between the active, dually n-octylated compounds and the lipid bilayer of the host cell can be postulated, to explain the observed inhibition of influenza virus attachment., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In order to obtain self assembling, multivalent ligand for influenza virus hemagglutinin α-N-acetylneuraminyl-(2-6)-D-galactopyranose has been synthesized and bonded to a water soluble fullerene derivative using 1,3-dipolar cycloaddition click reaction. The aggregating amphiphilic compound did not inhibit the influenza virus hemagglutinin, but it proved to be an inhibitor of its neuraminidase with a 50% inhibitory concentration of 81 μM., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Exo- and endocyclic double bonds of glycals and terminal double bonds of enoses were reacted with various thiols by irradiation with UV light in the presence of a cleavable photoinitiator. The photoinduced radical-mediated hydrothiolation reactions showed highly varying overall conversions depending not only on the substitution pattern and electron-density of the double bond but also on the nature and substitution pattern of the thiol partner. Out of the applied thiols thiophenol, producing the highly stabilized thiyl radical, exhibited the lowest reactivity toward each type of alkene. In most cases, the hydrothiolations took place with full regio- and stereoselectivities. Successful addition of 1,2 : 3,4-di-O-isopropylidene-6-thio-α-d-galactopyranose to a 2,3-unsaturated N-acetylneuraminic acid derivative, providing a (3 → 6)-S-linked pseudodisaccharide, demonstrated that the endocyclic double bond of Neu5Ac-2-ene, bearing an electron-withdrawing substituent, shows sufficient reactivity in the photoinduced thiol-ene coupling reaction.

Isoindole and benzoisoindole derivatives of ristocetin aglycon have been prepared by reaction with o-phthalaldehyde or naphthalene-2,3-dialdehyde and various thiols. The new compounds exhibited potent antibacterial and anti-influenza virus activity. The cluster forming and fluorescent properties of the aglycon derivatives were also studied., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

The primary amino function of teicoplanin pseudoaglycon has been transformed into arylthioisoindole or benzoisoindole and glycosylthioisoindole derivatives, in a reaction with o-phthalaldehyde or naphtalene-2,3-dicarbaldehyde and various thiols. All of the obtained semisynthetic antibiotics exhibited potent antibacterial activities against Gram-positive bacteria in the ng per ml concentration range. A few of them showed antiviral activity, in particular against influenza virus., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Free-radical hydrothiolation of the endocyclic double bond of enoses is reported. Reaction between 2-acetoxy-D-glucal and a range of thiols including amino acid, peptide, glycosyl thiols, and sugars with primary or secondary thiol functions gave S-linked α-glucoconjugates and S-disaccharides with full regio- and stereoselectivity. Addition of glycosyl thiols to a 2,3-unsaturated glycoside also proceeded with good selectivity and afforded a series of 3-deoxy-S-disaccharides.

We report on a new anti-influenza virus agent, SA-19, a lipophilic glycopeptide derivative consisting of aglycoristocetin coupled to a phenylbenzyl-substituted cyclobutenedione. In Madin-Darby canine kidney cells infected with influenza A/H1N1, A/H3N2, or B virus, SA-19 displayed a 50% antivirally effective concentration of 0.60 μM and a selectivity index (ratio of cytotoxic versus antiviral concentration) of 112. SA-19 was 11-fold more potent than unsubstituted aglycoristocetin and was active in human and nonhuman cell lines. Virus yield at 72 h p.i. was reduced by 3.6 logs at 0.8 μM SA-19. In contrast to amantadine and oseltamivir, SA-19 did not select for resistance upon prolonged virus exposure. SA-19 was shown to inhibit an early postbinding step in virus replication. The compound had no effect on hemagglutinin (HA)-mediated membrane fusion in an HA-polykaryon assay and did not inhibit the low-pH-induced refolding of the HA in a tryptic digestion assay. However, a marked inhibitory effect on the transduction exerted by retroviral pseudoparticles carrying an HA or vesicular stomatitis virus glycoprotein (VSV-G) fusion protein was noted, suggesting that SA-19 targets a cellular factor with a role in influenza virus and VSV entry. Using confocal microscopy with antinucleoprotein staining, SA-19 was proven to completely prevent the influenza virus nuclear entry. This virus arrest was characterized by the formation of cytoplasmic aggregates. SA-19 appeared to disturb the endocytic uptake and trap the influenza virus in vesicles distinct from early, late, or recycling endosomes. The aglycoristocetin derivative SA-19 represents a new class of potent and broad-acting influenza virus inhibitors with potential clinical relevance.

Glycopeptide antibiotic derivative teicoplanin ψ-aglycone has been bound covalently to a fullerenopyrrolidine derivative using azide-alkyne 1,3-dipolar cycloaddition reaction. The aggregation of the antibiotic-fullerene conjugate in aqueous solution has been studied. The conjugate exhibited antibacterial activity against enterococci resistant to teicoplanin., (Copyright © 2012. Published by Elsevier Masson SAS.)

1-Hydroxybisphosphonate derivatives of ciprofloxacin, gatifloxacin and moxifloxacin have been synthesized using Cu(I) catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction. The 1,2,3-triazol linked hydroxybisphosphonate derivative of ciprofloxacin exhibited antibacterial activity comparable to the parent antibiotic and all fluoroquinolone-bisphosphonates displayed osteotropic properties in a bone model., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Simple analogues of lipid II were synthesized from 3,4,6-tri-O-acetyl-2-acetamido-2-deoxy-1-thio-β-D-glucopyranose using conjugate addition onto ethylidene bisphosphonate and subsequent Wadsworth-Horner-Emmons reaction with long chain aliphatic aldehydes., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

New sugar derivatives of ristocetin were prepared by copper-catalyzed 1,3-dipolar cycloaddition reaction using azido-ristocetin aglycon and various propargyl glycosides. Some of them were found to be active against gram-positive bacteria and showed favorable antiviral activity against the H1N1 subtype of influenza A virus., (2010 Elsevier Ltd. All rights reserved.)

Semisynthetic, lipophilic ristocetin and teicoplanin derivatives were prepared starting from ristocetin aglycon and teicoplanin psi-aglycon (N-acetyl-D-glucosaminyl aglycoteicoplanin). The terminal amino functions of the aglycons were converted into azido form by triflic azide. Copper catalyzed 1,3-dipolar cycloaddition reaction with lipophilic alkynes resulted in the title compounds. Two of the teicoplanin derivatives showed very good MIC and MBC values against various Gram-positive bacteria, including vanA enterococci. The aggregation and interaction of a n-decyl derivative with bacterial cell wall components was studied. One of the lipophilic ristocetin derivatives displayed favorable anti-influenza virus activity.

Previous studies have demonstrated that glycopeptide compounds carrying hydrophobic substituents can have favorable pharmacological (i.e. antibacterial and antiviral) properties. We here report on the in vitro anti-influenza virus activity of aglycoristocetin derivatives containing hydrophobic side chain-substituted cyclobutenedione. The lead compound 8e displayed an antivirally effective concentration of 0.4 microM, which was consistent amongst influenza A/H1N1, A/H3N2 and B viruses, and a selectivity index > or =50. Structural analogues derived from aglycovancomycin were found to be inactive. The hydrophobic side chain was shown to be an important determinant of activity. The narrow structure-activity relationship and broad activity against several human influenza viruses suggest a highly conserved interaction site, which is presumably related to the influenza virus entry process. Compound 8e proved to be inactive against several unrelated RNA and DNA viruses, except for varicella-zoster virus, against which a favorable activity was noted.

The water-soluble N-methoxy-PEG-yl-, N-beta-D-glucopyranosyl- and N-beta-D-maltosylthioureido aglyco-ristocetin were prepared which, in contrast to ristocetin A, did not induce thrombocyte aggregation. The antibacterial activity of N-beta-D-maltosylthioureido aglyco-ristocetin A against MRSA was comparable to that of ristocetin A, while its activity against Enterococcus faecalis (VRE, TSE) is somewhat stronger when compared to those of vancomycin and ristocetin A.

The formation of supramolecular polymeric aggregates with a molecular mass of 100 kDa in a nonaqueous solution from a telechelic dimer of isopropylidene guanosine in the presence of K(+) ions is reported. The possible structure of macromonomers resulting from the development of G4 quartets was deduced from DOSY NMR, circular dichroism spectra, and dynamic light scattering measurements.

The aglycones of the antibiotics eremomycin, vancomycin and ristocetin (3, 4 and 6, respectively) were prepared by deglycosidation of the parent antibiotics with hydrogen fluoride, and complete assignation of their 1H, 13C and 15N spectra was performed. The squaric acid amide esters (11-14), were prepared from dimethyl squarate. The corresponding asymmetric diamides (16-19, 22, 23) were also synthesized using 4-phenylbenzylamine and triglycine. The advantage of the method is the high regioselectivity and that no protecting group strategy is required. Electrospray mass spectroscopic method was elaborated for the determination of the site of substitution of the modified antibiotics. The antibacterial activity of the prepared compounds is discussed in detail.

Deoxy-ATP is a potent inducer of apoptosis. We intended to synthesize a lipophilic dAMP derivative which, according to our working hypothesis penetrates into the cell, is converted to dAMP by intracellular esterases and to dATP by nucleotide kinases. We synthesized dAMP-di-n-butylester (DAB) and tested it. We found that it fulfills the above-described expectations. DAB treatment decreases the viability of HL-60 cells, increases the dATP concentration and induces apoptogenic cytochrome c release from mitochondria with concomitant elevation of caspase-9 activity. Our results indicate that use of dAMP derivatives with masked phosphate may be a feasible approach for pharmacological elevation of intracellular dATP and induction of apoptosis.

Treatment of the squaric acid amide esters (7, 9) of anthracycline glycoside antibiotics with aliphatic and aromatic primary and secondary amines, amino acids, peptides and aminodeoxy sugars furnished the new asymmetric diamides 16-19, 25-30, 32, 34 and 38-40 in stereoselective reactions which do not require protecting group-manipulations. The IC50 = 0.12 microM value measured for daunorubicin (1) on human leukemia (HL-60) cells is comparable to those obtained for the daunomycin-L-leucyl squaric acid diamide (30, IC50 = 0.18 microM) and the corresponding D-galactosamine derivative (40, IC50=0.22 microM).

The reaction of the anthracycline glycoside antibiotics 1-3 with the squaric acid ester 4 gave the squaric acid amide esters 5-7 under neutral conditions, whereas over pH7 the products are the symmetric diamides (8, 9, 11, and 12). Of the prepared compounds 11 was the most active on MCF-7 human mammary adenocarcinoma cells.

From January 1976, 50 patients with squamous cell cancer of the head and neck were treated with telecobalt preoperative irradiation followed by appropriate surgery. Another group of 50 patients, who matched in risk factors and stage of disease, were treated with preoperative chemotherapy and surgery. Chemotherapy consisted of bleomycin, vincristine, mitolactol and methotrexate. All patients received 3 courses. Surgery was performed 2-3 weeks post-chemotherapy or 4-6 weeks postradiotherapy. Forty-four percent of the patients in the radiotherapy group showed recurrences, while 30% of the patients had recurrence in the chemotherapy group. The overall 3-year survival rate was 66% in the chemotherapy group and 57% in the radiation therapy group, with no statistical difference.

Results of the combined (irradiation + surgical) treatment of 33 patients, in great majority with advanced mouth cavity flattened epithelium are reported on. With 45% of the patients a 3 years survival could be obtained. The mainly radical surgical interventions were carried out after big dose preoperative irradiation treatment (Co. 60).