Abstract: 2-Benzylideneglutaraldehydes of the formula ##STR1## where R.sup.1, R.sup.2 and R.sup.3 independently are hydrogen or a substituent selected from the group consisting of halo, lower-alkyl, phenyl, carboxy, lower-alkoxycarbonyl, phenoxycarbonyl, aminocarbonyl, hydroxysulfonyl, nitro, cyano, hydroxy, loweralkoxy and phenoxy, a method of use thereof as disinfectants, disinfectant compositions comprising them, and 2,6-dialkoxy-3-(.alpha.-alkoxybenzyl)tetrahydropyrans of the formula ##STR2## where R.sup.1, R.sup.2 and R.sup.3 are as defined above and R.sup.4 and R.sup.5 independently are alkyl of one to four carbon atoms, which are intermediates for their preparation are disclosed.

Abstract: Disclosed is a method of disinfecting and a method for destroying bacteria and fungi employing certain 2-substituted glutaraldehydes having the formulas ##STR1## wherein R.sup.1 is selected from the group consisting of alkyl having from one to twelve carbon atoms, lower-alkoxyalkyl having from two to twelve carbon atoms, cycloalkyl having from three to twelve ring carbon atoms, and alkyl-substituted cycloalkyl having from three to eight ring carbon atoms and a total of from four to ten carbon atoms, and R.sup.3 is alkyl having from one to four carbon atoms.

Abstract: 2-Benzylideneglutaraldehydes of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 independently are hydrogen or a substituent selected from the group consisting of halo, lower-alkyl, phenyl, carboxy, lower-alkoxycarbonyl, phenoxycarbonyl, aminocarbonyl, hydroxysulfonyl, nitro, cyano, hydroxy, lower-alkoxy and phenoxy, a method of use thereof as disinfectants, disinfectant compositions comprising them, and 2,6-dialkoxy-3-(.alpha.-alkoxybenzyl)tetrahydropyrans of the formula ##STR2## where R.sup.1, R.sup.2 and R.sup.3 are as defined above and R.sup.4 and R.sup.5 independently are alkyl of one to four carbon atoms, which are intermediates for their preparation are disclosed.