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Benzoxonium chloride belongs to the group of quaternary ammonium salts, which have been widely used for decades as disinfectants because of their high efficacy, low toxicity, and thermal stability. In this study, we have prepared the C10-C18 set of benzoxonium-like salts to evaluate the effect of their chemical and biological decontamination capabilities. In particular, biocidal activity against a panel of bacterial strains including Staphylococcus aureus in biofilm form was screened. In addition, the most promising compounds were successfully tested against Francisella tularensis as a representative of potential biological warfare agents. From a point of view of chemical warfare protection, the efficiency of BOC-like compounds to degrade the organophosphate simulant fenitrothion was examined. Notwithstanding that no single compound with universal effectiveness was identified, a mixture of only two compounds from this group would be able to satisfactorily cover the proposed decontamination spectrum. In addition, the compounds were evaluated for their cytotoxicity as a basic safety parameter for potential use in practice. In summary, the dual effect on chemical and biological agents of benzoxonium-like salts offer attractive potential as active components of decontamination mixtures in the case of a terrorist threat or chemical or biological accidents.

The reaction of methyl 2,3:4,6-di- O -benzylidene-α- D -mannopyranoside ( 5 ) with N -bromosuccinimide gave mainly three, isomeric dibromo dibenzoates, identified as the 3,6-dibromo- altro ( 1 ), 3,6-dibromo- manno ( 2 ), and 4,6-dibromo- ido ( 3 ) derivatives by subsequent chemical transformation and by extended n.m.r.-spectral studies. The reaction of methyl 2,3:4,6- O -benzylidene-α- D -allopyranoside ( 22 ) with N -bromosuccinimide gave two isomeric dibromo dibenzoates, the 2,6-dibromo- altro ( 23 ) and 3,6-dibromo- gluco ( 24 ) products, and their structures were similarly assigned. A similar reaction-sequence with methyl 2,3:4,6-di- O -benzylidene-α- D -glucopyranoside ( 32 ), however, yielded two isomeric monobenzoates 33 and 34 , which could be identified straightforwardly. The results are consistent with the intermediate formation of benzoxonium ions that undergo favored axial attack. Thus the observed products and their ratios in reactions of 5 and of 22 with N -bromo-succinimide are explicable. Compound 32 , however, does not appear to react by way of an intermediate, five-membered 2,3- trans benzoxonium ion.

Aquilibrierungsversuche in Nitromethan zeigen, das von den vier Acetoxonium-Ionen das gluco-Ion 5 zu 60%, das manno-Ion 6 zu 12%, das altro-Ion 7 zu 7% und das ido-Ion 8 zu 21 % im Gleichgewicht vorliegen. Einheitliches Idose-4.6-Acetoxonium-Salz 8 kristallisiert aus CH2Cl2, da es uber das Gleichgewicht 5⇋6⇋7⇋8 standig nachgebildet wird. Das Glucose-1.2-Acetoxonium-Salz 5 kann durch Fallung aus CCl4 bei −10° erhalten werden. Penta-O-benzoyl-α-D-idopyranose (15) ist durch Benzoxonium-Umlagerung aus Glucose gewinnbar. Tetra-O-acetyl-6-brom-6-desoxy-α-D-idopyranose (16) wird durch „trans” Offnung des Idose-4.6-Acetoxonium-Salzes 8 mit LiBr dargestellt. Carboxonium Compounds in Carbohydrate Chemistry, X. Investigations on Acetoxonium Rearrangement of D -Glucose to D-Idose Equilibration experiments in nitromethane show that in equilibrium of the four acetoxonium ions the gluco-ion 5 is present in 60%, the manno-ion 6 in 12%, the altro-ion 7 in 7% and the ido-ion 8 in 21 %. Pure idose-4,6-acetoxonium salt 8 crystallizes from CH2Cl2 as it is formed from the equilibrium 5⇋6⇋7⇋8. The glucose-1,2-acetoxonium salt 5 is precipitated in CCl4 at −10°C. Penta-O-benzoyl-α-D-idopyranose (15) is obtained by benzoxonium rearrangement from glucose. Tetra-O-acetyl-6-bromo-6-deoxy-α-D-idopyranose (16) is formed by „trans”-opening of the idose-4,6-acetoxonium salt 8 with LiBr.

The reaction of 2',3'-0-benzylideneuridine with N-bromosuccinimide (NBS) leads to 3'-0-benzoyl-2',5dibromouridine. The stereoselectivity of bromination in the sugar ring can be explained by invoking the sequential formation of benzoxonium ion and 2,2'-anhydronucleoside intermediates. Protonation of the appropriate 2,2'-anhydronucleoside, followed by treatment with NBS, recreates the conditions which prevail in the original reaction of the benzylidene acetal with NBS.