Sawhorse Projection Formula

The sawhorse projection draws the carbon-carbon bond of interest diagonally across the page, slightly elongated, rather than head-on. By convention, the carbon drawn at the lower-left end of that diagonal bond is understood to be the FRONT carbon (nearer the viewer), and the carbon at the upper-right end is the BACK carbon (further from the viewer); each carbon's other three bonds then radiate outward from its own end of the diagonal. This projection exists specifically because the Fischer projection, useful as it is, does a poor job of showing the true spatial relationship between substituents on two ADJACENT atoms (as i …