in spite of the high sensitivity of the analytical method ( limit of detection for fosfestrol 0.1 micrograms/ml and for e-des and its mono-conjugates 2-5 ng/ml ) neither fosfestrol nor e-des-monophosphate are detectable in plasma due to the biotransformation of fosfestrol , which is already metabolized by the enzymes of the gut wall .
C0060692
0
C0012203
e-des