\documentclass[12pt,border=1pt,crop,multi=false,tikz,class=scrartcl]{standalone}
\usepackage{chemfig,chemmacros}
\usepackage{color}
\usepackage{xcolor}

\renewcommand*{\familydefault}{\sfdefault}
\renewcommand*\printatom[1]{\ensuremath{\mathsf{#1} } }
\setatomsep{2em}
\setdoublesep{.6ex}
\setarrowdefault{,1.2, thick}
\setbondstyle{thick,cap=round}

\makeatletter
% From: http://tex.stackexchange.com/a/125761
% Initial arguments:
% #1, #2: Same as for -U> (above arrow)
% #3: Additional label at midpoint (also above arrow)
% #4, #5, #6: Like #1, #2, and #3, but below arrow
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\makeatother
 
\pagestyle{empty}
\thispagestyle{empty}
\begin{document}
\schemestart[][west]
	\chemname{\chemfig{
		P(=[2]O)(-[:150]HO)(-[:210]HO)-[:-30]O-[:30]-[::-60](-[::-60]OH)-[::60](=[::60]O)-[::-60]OH}
	}{\color{blue}3--phosphoglycerate}
	\arrow{-X>[\ch{NAD}\pch][\ch{H}\pch+\\\ch{NADH}][][][][\color{purple}EC 1.1.1.95]}[,2.5]
	\chemname{\chemfig{
		P(=[2]O)(-[:150]HO)(-[:210]HO)-[:-30]O-[:30]-[::-60](=[::-60]O)-[::60](=[::60]O)-[::-60]OH}
	}{\color{blue}3--phosphohydroxypyruvate}
	\arrow{-X>[*{0}\ch{L-glutamate}][*{0}2\ch{-oxoglutarate}][][][][*{0}\color{purple}EC 2.6.1.52]}[-90,1.5]
	\chemname{\chemfig{
		P(=[2]O)(-[:150]HO)(-[:210]HO)-[:-30]O-[:30]-[::-60](-[::-60]NH_2)-[::60](=[::60]O)-[::-60]OH}
	}{\color{blue}O--phosphoserine}
	\arrow{-X>[][][\color{purple}EC 3.1.3.3][\ch{H2O}][\ch{P_i}][][-2ex]}[-180,2]
	\chemname{\chemfig{
		HO-[:30]-[::-60](-[::-60]NH_2)-[::60](=[::60]O)-[::-60]OH}
	}{\color{blue}serine}
\schemestop
\end{document}