Stacking molecules vertically

Question

I've been using Chemfig to try to draw the following image:

So far, this is what I've been able to get:

I'd like to be able to stack the 3 Biodiesel molecules vertically like the original picture, but how would I edit my code?

\schemestart
\chemname{\chemfig{CHOOCR''(-[2]CH_2OOCR')(-[6]CH_2OOCR''')}}{Triglyceride}
\+
\chemname{\chemfig{3CH_3OH}}{Methanol}
\arrow{<=>[Catalyst]}
\chemname{\chemfig{R'COOCH_3} \+ \chemfig{R''COOCH_3} \+ \chemfig{R'''COOCH_3}}{Biodiesel}
\+
\chemname{\chemfig{CHOH(-[2]CH_2OH)(-[6]CH_2OOH)}}{Glycerol}
\schemestop

I've taken a look at the following: Reaction sheme for Saponification with chemfig: horizontal and vertical placement

Arranging vertical reaction with "plus(+)" in chemfig scheme

Chemfig: how to write vertically?

Answer 1

This is probably not the most elegant solution, using a lot of invisible arrows but…

\documentclass{article}
\usepackage{chemfig}
\begin{document}

\schemestart
  \chemname{\chemfig{CHOOCR''(-[2]CH_2OOCR')(-[6]CH_2OOCR''')}}{Triglyceride}
  \+
  \chemnameinit{}
  \chemname{\chemfig{3CH_3OH}}{Methanol}
  \arrow(.base east--bio.base west){<=>[Catalyst][][4pt]}
  \chemfig{R''COOCH_3}
  \arrow(.base east--.base west){0}[,0]
  \+
  \chemnameinit{}
  \chemname{\chemfig{CHOH(-[2]CH_2OH)(-[6]CH_2OOH)}}{Glycerol}
  \arrow(@bio--){0}[90,.15]
  \+
  \arrow{0}[90,.15]
  \chemfig{R'COOCH_3}
  \arrow(@bio--){0}[-90,.15]
  \+
  \arrow{0}[-90,.15]
  \chemnameinit{}
  \chemname{\chemfig{R'''COOCH_3}}{Biodiesel}
\schemestop

\end{document}