The present invention relates to the use of compounds of the general Formula (XIII): wherein A.sup.7 is C.dbd.O, C.dbd.S, SO.sub.2, CH--OR.sup.13, C.dbd.NR.sup.12, or CH.sub.2--CHOR.sup.13; A.sup.8 is C(R.sup.14).sub.2, O, S, or NR.sup.12; A.sup.9 is C.dbd.O, C.dbd.S, SO.sub.2, CH--OR.sup.13, C.dbd.NR.sup.12, or CH.sub.2--CHOR.sup.13; m is 0, or 1 q is 0, or 1 r is 0, or 1 R.sup.12 is H, CH.sub.3, CH.sub.2--CH.sub.3, C.sub.6H.sub.5, OCH.sub.3, OCH.sub.2--CH.sub.3, OH, or SH; R.sup.13 is H, CH.sub.3, or CH.sub.2--CH.sub.3; R.sup.14 is H, alkyl, alkoxy, OH, or SH;