−SO3H;81-\mathrm{SO}_{3} \mathrm{H} ; 81−SO3H;81
−NH2;100-\mathrm{NH}_{2} ; 100−NH2;100
−x;74-x ; 74−x;74
−CH3; None of them -\mathrm{CH}_{3} ; \text { None of them }−CH3; None of them