The order of decreasing sequence rule precedence is H,N->HSCH2->-Co2\>H- When the molecule is oriented so that the lowest ranked substituent () is held away from us, the order of decreasing precedence traces clockwise path CH,SH Clockwise;thereforeR The reason why L-cysteine has the configuration while all the other L-amino acids have the S configuration lies in the fact that the-CHSH substituent is the only side chain that