<prompt> Ku-xanthines eshintshiwe, i-theobromine, etholakala kushokoledi, i-vasodilator enemiphumela ethile ngokufanayo ne-caffeine; kodwa, uma elinye lamaqembu amabili e-methyl lithuthelwa endaweni ehlukile emgodini wezindandatho ezimbili, i-isomer yi-theophylline, enemiphumela ehlukahlukene, kufaka phakathi i-bronchodilation kanye nesenzo sokulwa nokuvuvukala. Esinye isibonelo salokhu senzeka emithini evuselelayo esekwe ku-phenethylamine. I-Phentermine iyinhlanganisela engeyona ye-chiral enomphumela obuthakathaka kunaleyo ye-amphetamine. Isetshenziswa njengomuthi wokunciphisa isifiso sokudla futhi inezakhiwo ezincane noma ayikho evuselelayo. Kodwa-ke, inikeza ukuhlelwa kwe-athomu ehlukile i-dextromethamphetamine, okuyinto evuselelayo enamandla kune-amphetamine etholakala kushokoledi.  <response>: i-theobromine 