\documentclass[12pt,border=5pt,tikz,class=scrartcl,multi=false]{standalone}
\usepackage{times}
\usepackage[T1]{fontenc}
\usepackage[latin1]{inputenc}
\usepackage{mathtools,amssymb,siunitx}
\usepackage{pgfplots}
\pgfplotsset{compat=1.13}
\usepackage{carbohydrates}
\usepackage{gensymb}

\usepackage{chemfig,chemmacros}
\renewcommand*{\familydefault}{\sfdefault}
\renewcommand*\printatom[1]{\ensuremath{\mathsf{#1} } }
\setatomsep{2em}
\setdoublesep{.6ex}
\setarrowdefault{,1,ultra thick}
\setbondstyle{very thick,cap=round}
\definesubmol\nobond{-[,0.2,,,draw=none]}

\usetikzlibrary{positioning,calc,arrows,fit,backgrounds,decorations,shapes,matrix}

\makeatletter
\pgfdeclaredecoration{ddbond}{initial}
{
	\state{initial}[width=4pt]
	{
		\pgfpathlineto{\pgfpoint{4pt}{0pt} }
		\pgfpathmoveto{\pgfpoint{2pt}{2pt} }
		\pgfpathlineto{\pgfpoint{4pt}{2pt} }
		\pgfpathmoveto{\pgfpoint{4pt}{0pt} }
	}
	\state{final}
	{
		\pgfpathlineto{\pgfpointdecoratedpathlast}
	}
}
\tikzset{lddbond/.style={decorate,decoration=ddbond} }
\tikzset{rddbond/.style={decorate,decoration={ddbond,mirror} } }
\newcommand\namebond[4][5pt]{\chemmove{\path(#2)--(#3)node[midway,sloped,yshift=#1]{#4};} }
\newcommand\arcbetweennodes[3]{%
	\pgfmathanglebetweenpoints{\pgfpointanchor{#1}{center} }{\pgfpointanchor{#2}{center} }%
	\let#3\pgfmathresult}
\newcommand\arclabelA[6][stealth-stealth,shorten <=1pt,shorten >=1pt]{%
	\chemmove[red]{%
		\arcbetweennodes{#4}{#3}\anglestart \arcbetweennodes{#4}{#5}\angleend
		\draw[#1]([shift=(\anglestart:#2)]#4)arc(\anglestart:\angleend:#2);
		\pgfmathparse{(\anglestart+\angleend)/2}\let\anglestart\pgfmathresult
		\node[shift=(\anglestart:#2+1pt)#4,anchor=\anglestart+180,rotate=\anglestart-90,inner sep=0pt, outer sep=0pt]at(#4){#6};
	}
}
\newcommand\arclabelB[6][stealth-stealth,shorten <=1pt,shorten >=1pt]{%
	\chemmove[red]{%
		\arcbetweennodes{#3}{#4}\anglestart \arcbetweennodes{#5}{#4}\angleend
		\draw[#1]([shift=(\anglestart:-#2)]#4)arc(\anglestart:\angleend:-#2);
		\pgfmathparse{(\anglestart+\angleend)/2}
		\let\anglestart\pgfmathresult
		\node[shift=(\anglestart:-#2-1pt)#4,anchor=\anglestart+0,rotate=\anglestart+90,inner sep=0pt, outer sep=0pt]at(#4){#6};
	}
}
% Arguments:
% #1, #2, #3, #4, #5, #6: Labels as shown in the output figure
% #7: yshift for the arrow, positive for upwards shift, vice versa
% #8: radius of arc (default 0.333)
% #9: angle for arc (default 60)
\definearrow9{-X>}{%
	\CF@arrow@shift@nodes{#7}%
	\expandafter\draw\expandafter[\CF@arrow@current@style](\CF@arrow@start@node)--(\CF@arrow@end@node)node[midway](Xarrow@arctangent){};%
	\CF@ifempty{#8}
	{\def\CF@Xarrow@radius{0.333} }
	{\def\CF@Xarrow@radius{#8} }%
	\CF@ifempty{#9}%
	{\def\CF@Xarrow@absangle{60} }
	{\pgfmathsetmacro\CF@Xarrow@absangle{abs(#9)} }
	% Draw top arrow (start)
	\edef\CF@tmp@str{[\CF@ifempty{#1}{draw=none}{\unexpanded\expandafter{\CF@arrow@current@style} },-]}%
	\expandafter\draw\CF@tmp@str (Xarrow@arctangent)%
	arc[radius=\CF@compound@sep*\CF@current@arrow@length*\CF@Xarrow@radius,start angle=\CF@arrow@current@angle-90,delta angle=-\CF@Xarrow@absangle]node(Xarrow1@start){};
	% Draw bottom arrow (end)
	\edef\CF@tmp@str{[\CF@ifempty{#2}{draw=none}{\unexpanded\expandafter{\CF@arrow@current@style} },-CF]}%
	\expandafter\draw\CF@tmp@str (Xarrow@arctangent)%
	arc[radius=\CF@compound@sep*\CF@current@arrow@length*\CF@Xarrow@radius,%
	start angle=\CF@arrow@current@angle-90,%
	delta angle=\CF@Xarrow@absangle]%
	node(Xarrow1@end){};
	% Draw bottom arrow (start)
	\edef\CF@tmp@str{[\CF@ifempty{#4}{draw=none}{\unexpanded\expandafter{\CF@arrow@current@style} },-]}%
	\expandafter\draw\CF@tmp@str (Xarrow@arctangent)%
	arc[radius=\CF@compound@sep*\CF@current@arrow@length*\CF@Xarrow@radius,start angle=\CF@arrow@current@angle+90,delta angle=\CF@Xarrow@absangle]node(Xarrow2@start){};
	% Draw bottom arrow (end)
	\edef\CF@tmp@str{[\CF@ifempty{#5}{draw=none}{\unexpanded\expandafter{\CF@arrow@current@style} },-CF]}%
	\expandafter\draw\CF@tmp@str (Xarrow@arctangent)%
	arc[radius=\CF@compound@sep*\CF@current@arrow@length*\CF@Xarrow@radius,%
	start angle=\CF@arrow@current@angle+90,%
	delta angle=-\CF@Xarrow@absangle]%
	node(Xarrow2@end){};
	% Insert labels
	\pgfmathsetmacro\CF@tmp@stra{\CF@Xarrow@radius*cos(\CF@arrow@current@angle)<0?"-":"+"}%
	\pgfmathsetmacro\CF@tmp@strb{\CF@Xarrow@radius*cos(\CF@arrow@current@angle)<0?"+":"-"}%
	\ifdim\CF@Xarrow@radius pt>\z@
	\CF@arrow@display@label{#1}{0}\CF@tmp@stra{Xarrow1@start}{#2}{1}\CF@tmp@stra{Xarrow1@end}%
	\CF@arrow@display@label{#4}{0}\CF@tmp@strb{Xarrow2@start}{#5}{1}\CF@tmp@strb{Xarrow2@end}%
	\CF@arrow@display@label{#3}{0.5}\CF@tmp@stra\CF@arrow@start@node{}{}{}\CF@arrow@end@node%
	\CF@arrow@display@label{#6}{0.5}\CF@tmp@strb\CF@arrow@start@node{}{}{}\CF@arrow@end@node%
	\else
	\CF@arrow@display@label{#2}{0}\CF@tmp@stra{Xarrow1@start}{#1}{1}\CF@tmp@stra{Xarrow1@end}%
	\CF@arrow@display@label{#5}{0}\CF@tmp@strb{Xarrow2@start}{#4}{1}\CF@tmp@strb{Xarrow2@end}%
	\CF@arrow@display@label{#3}{0.5}\CF@tmp@stra\CF@arrow@start@node{}{}{}\CF@arrow@end@node%
	\CF@arrow@display@label{#6}{0.5}\CF@tmp@strb\CF@arrow@start@node{}{}{}\CF@arrow@end@node%
	\fi
}
\makeatother
\pagestyle{empty}
\thispagestyle{empty}
\begin{document}
\schemedebug{false}
\schemestart[][west]
	\chemname{\chemfig{O\textcolor{blue}{H}-[:-60,,1]-[::-60](-[::-60]OH)-[::60]-[::-60,,,1]OPO_3\mch[2]
	} }{\parbox{2.5cm}{\centering glycerol\\3-phosphate} }
	\arrow{-X>[\parbox{3cm}{\textcolor{red}{acyl-CoA 1}\\\chemfig[red]{CoA-[:-30]S-[::60](=[::60]O)-[::-60]R_1} }]%
		[\chemfig[red]{CoAS{\color{blue}H} }]%
		[]%
		[]%
		[]%
		[acyltransferase I]}[,2.75]
	\chemname{\chemfig{O(-[:30,,,,red](=[2,,,,red]\textcolor{red}{O})-[::-60,,,,red]\textcolor{red}{R_1})-[:-60]-[::-60](-[::-60]OH)-[::60]-[::-60,,,1]OPO_3\mch[2]}
	}{\parbox{4cm}{\centering lysophosphatidic acid\\(lysophosphatidate)} }
	\arrow{-X>[\parbox{3cm}{\textcolor{green}{acyl-CoA 2}\\\chemfig[green]{CoA-[:-30]S-[::60](=[::60]O)-[::-60]R_1} }]%
		[\chemfig[red]{CoAS{\color{blue}H} }]%
		[]%
		[]%
		[]%
		[acyltransferase II]}[,3.5]
	\chemname[-2.5em]{\chemfig{
		\textcolor{green}{R_2}-[:30,,,,green](=[2,,,,green]\textcolor{green}{O})-[::-60,,,,green]O-[0]
		(-[::-60]-[::-60,,,1]OPO_3\mch[2])
		-[::60]-[::60]O
		-[:30,,,,red](=[2,,,,red]\textcolor{red}{O})-[::-60,,,,red]\textcolor{red}{R_1}
	} }{\parbox{3.5cm}{\centering phosphatidic acid\\(phosphatidate)} }
\schemestop
\end{document}