This application is directed to compounds of the formula ##EQU1## wherein R.sup.1 is lower alkyl; R.sup.2 is hydrogen, lower alkyl or ##EQU2## wherein m is a whole number 2 to 5, n is a whole number 1 to 4 and Y is hydrogen, --OH or --COOR wherein R is hydrogen or lower alkyl; and X is ##EQU3## wherein R.sup.3 is hydrogen or ##EQU4## wherein n and Y have the same meaning given above, R.sup.4 is ##EQU5## wherein n and Y have the same meaning given above and R.sup.5 is lower alkyl. These compounds are useful as silver halide solvents in photography.
Alkanes containing an intralinear sulfonyl group and an intralinear 1-piperazinylsulfonamido group separated by a single carbon substituted with at least one hydrogen atom are employed as silver halide solvents in photographic processes and compositions.
Difunctional compounds wherein one of said functions is a hard or soft atom that ionizes to the corresponding anion in alkaline solution to combine with silver cation and the other of said functions is a non-ionizable soft base that additionally combines with said silver cation are employed as silver halide complexing agents in photography. In a preferred embodiment, the difunctional compounds possess (a) an O, N or C atom that ionizes to the corresponding O.sup..crclbar., N.sup..crclbar. or C.sup..crclbar. anion in basic solution and (b) an --S-- containing moiety excluding --SH and moieties that form --S.sup..crclbar. in basic solution wherein the --S-- of said moiety is positioned alpha, beta, gamma, delta, epsilon or zeta to said anion.
