(E)-6-[3-(tert-butylcarbamoylamino)phenyl]-6-pyridin-3-ylhex-5-enoic acid (E)-6-[3-(tert-butylcarbamoylamino)phenyl]-6-(3-pyridyl)hex-5-enoic acid (E)-6-[3-[[(tert-butylamino)-oxomethyl]amino]phenyl]-6-(3-pyridyl)hex-5-enoic acid (E)-6-[3-(tert-butylcarbamoylamino)phenyl]-6-pyridin-3-yl-hex-5-enoic acid