Jul.  30,  2020  4  US 2020/0241417 Al  [0045]  The C$_{2}$ -C$_{8 }$ alkenyl group may be straight, branched  or cyclic, and examples thereof include vinyl, 1-propenyl,  2-propenyl, butenyl, hexenyl and cyclohexenyl.  [0046]  Among others, R 1  is preferably fluorine, chlorine,  bromine, hydroxyl, amino,  C$_{1 }$-C$_{3 }$ alkyl,  C$_{1 }$-C$_{3 }$ alkoxy,  C$_{2}$-C$_{4 }$ acyloxy, -NR $^{1}$A----C(=O)-R1 B  or -NR $^{1}$A----C(=O)› O-R  lB.  When m is 2 or more, a plurality of groups R $^{1 }$may  be the same or different.  [0047]  In formulae (A-1) and (A-2), R 2  and R 3  are each  independently a C$_{1 }$-C$_{6 }$ alkyl group, R  1  and R 3  may bond  together to form a ring with the carbon atom to which they  are attached. R 4  and R 6  are each independently hydrogen, a  C$_{1 }$-C$_{4 }$ straight or branched alkyl group,  C$_{2}$-C$_{12 }$ straight or  branched alkoxycarbonyl group, C$_{1 }$-C$_{1}$s aryloxycarbonyl  group, or  CcC$_{14 }$ aralkyloxycarbonyl group. Rs is a  C$_{1 }$-C$_{6 }$ alkyl group,  C$_{2}$-C$_{6 }$ alkenyl group,  C$_{2}$-C$_{6 }$ alkynyl group, or  C$_{6}$-C$_{12 }$aryl group.  [0048]  The  C$_{1 }$-C$_{6 }$ alkyl and  C$_{2}$-C$_{6 }$ alkenyl groups may be  straight, branched or cyclic, and examples thereof are as  exemplified above. Examples of the C$_{1 }$-C$_{4 }$ straight or  branched alkyl group include those exemplified above which  are straight or branched and have 1 to 4 carbon atoms. The  C$_{2}$ -C$_{6 }$ alkynyl group may be straight, branched or cyclic and  examples thereof include ethynyl, propynyl, and butynyl.  Examples of the  CcC$_{12 }$ aryl group include phenyl, tolyl,  xylyl, 1-naphthyl and 2-naphthyl.  [0049]  Examples of the C$_{2}$-C$_{12 }$ straight or branched  alkoxycarbonyl group include methoxycarbonyl, ethoxycar› bonyl, n-propyloxycarbonyl, isopropyloxycarbonyl, n-buty› loxycarbonyl, isobutyloxycarbonyl, sec-butyloxycarbonyl,  tert-buty loxycarbony 1, n-penlty loxycarboy 1, sec-peutyloxy› carbony 1,  tert-penty loxycarbouy 1,  neopenty loxycarbony 1,  n-hexyloxycarbonyl, n-heptyloxycarbonyl, n-octyloxycar› bonyl, 2-ethylhexyloxycarbonyl, n-nonyloxycarbonyl, n-de› cyloxycarbonyl, n-undecyloxycarbonyl, n-dodecyloxycar› bony 1,  n-tridecy loxycarbony 1,  n-pentadecyloxycarbony 1,  vinyloxycarbonyl, 1-propenyloxycarbonyl, and 2-propeny› loxycarbony I.  [0050]  Among others, R 2  and R 3  are preferably C$_{1}$-C$_{3 }$ alkyl groups. Rs is preferably a  C$_{1 }$-C$_{6 }$ alkyl,  C$_{2}$-C$_{4 }$ alkenyl,  or C$_{2}$ -C$_{4 }$ alkynyl group. R$^{1 }$and R$^{6 }$are preferably hydrogen,  C$_{1 }$-C$_{4 }$ straight or branched alkyl groups, or  C$_{2}$-C$_{6 }$ straight or  branched alkoxycarbonyl groups.  [0051]  In formulae (A-1) and (A-2), Risa C$_{2}$ -C$_{10 }$alicyclic  group to form a ring with the nitrogen atom in the formula.  Examples of the ring R include cyclic hydrocarbons such as  cyclopropane, cyclopentane, cyclohexane, norbomane and  adamantane, in which one carbon atom is replaced by  nitrogen atom.  [0052]  In formulae (A-1) and (A-2), mis an integer of 1  to 5, n is an integer of 0 to 4, and 1 sm+ns5, preferably m  is an integer of 2 to 4 and n is 0 or 1; and pis 1 or 2.  [0053]  Examples of the amine compound having formula  (A-1) are shown below, but not limited thereto.  -continued  b-<+o 