Tetrahydroisoquinoline compounds and fungicides containing the same

A fungicide composition comprising an effective amount of a tetrahydroisoquinoline derivative of the formula ##STR71## where R.sup.1 represents a C.sub.1 -C.sub.5 straight or branched alkyl, C.sub.2 -C.sub.5 straight or branched alkenyl or C.sub.2 -C.sub.5 straight or branched alkynyl;

• R.sup.2 represents a C.sub.1 -C.sub.10 straight or branched alkyl, C.sub.3 -C.sub.10 straight or branched alkenyl, C.sub.2 -C.sub.10 straight or branched alkynyl, C.sub.1 -C.sub.10 straight or branched alkoxy, C.sub.2 -C.sub.10 straight or branched alkenyloxy, C.sub.2 -C.sub.10 straight or branched alkynyloxy, or C.sub.1 -C.sub.10 straight or branched halogenated alkyl;
• R.sup.3, R.sup.4, R.sup.5 and R.sup.6, which may be the same or different, each represent a hydrogen atom, C.sub.1 -C.sub.10 straight or branched alkyl, C.sub.2 -C.sub.10 straight or branched alkenyl, C.sub.2 -C.sub.10 straight or branched alkynyl, C.sub.1 -C.sub.10 straight or branched alkoxy, C.sub.2 -C.sub.10 straight or branched alkenyloxy, C.sub.2 -C.sub.10 straight or branched alkynyloxy or halogen atom, provided that R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are not simultaneously hydrogen atoms and R.sup.4 and R.sup.5 are not simultaneously methoxy groups or an acid addition salt thereof in an agriculturally acceptable carrier.

A method of treating fungal infestations on plants comprising applying to plants a fungicidally effective amount of a tetrahydroisoquinoline compound of the formula:

• ##STR72## where R.sup.1 represents a C.sub.1 -C.sub.5 straight or branched alkyl, C.sub.2 -C.sub.5 straight or branched alkenyl or C.sub.2 -C.sub.5 straight or branched alkynyl;
• R.sup.2 represents a C.sub.1 -C.sub.10 straight or branched alkyl, C.sub.3 -C.sub.10 straight or branched alkenyl, C.sub.2 -C.sub.10 straight or branched alkynyl, C.sub.1 -C.sub.10 straight or branched alkoxy, C.sub.2 -C.sub.10 straight or branched alkenyloxy, C.sub.2 -C.sub.10 straight or branched alkynyloxy, or C.sub.1 -C.sub.10 straight or branched halogenated alkyl;
• R.sup.3, R.sup.4, R.sup.5 and R.sup.6, which may be the same or different, each represent a hydrogen atom, C.sub.1 -C.sub.10 straight or branched alkyl, C.sub.2 -C.sub.10 straight or branched alkenyl, C.sub.2 -C.sub.10 straight or branched alkynyl, C.sub.1 -C.sub.10 straight or branched alkoxy, C.sub.2 -C.sub.10 straight or branched alkenyloxy, C.sub.2 -C.sub.10 straight or branched alkynyloxy or halogen atom, provided that R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are not simultaneously hydrogen atoms and R.sup.4 and R.sup.5 are not simultaneously methoxy groups or an acid addition salt thereof.