Vertical alignment in chemical reaction using chemfig

Question

I was trying to write an equation using chemfig.However,the + sign is not aligned properly. Also, how do I make the bonds from Me to (<-O) and (-O) longer so the bond length between C and N are longer.

I use the code below.

\begin{center}
  \schemestart[][184]
  \subscheme{
    \setatomsep{2.5em}
    \chemfig{Me-OH}
    \arrow{0}[,0]\+
    \chemfig{C(=[:150]O)(-[:30]R)(-[:270,,,,]N(-[:330,,,,]H)(-[:210,,,,]{OH}))}
    \arrow
    }
    \subscheme
    {
    \chemfig{Me(-[:45,,,,<-]O(=[:330,,,,]C?(-[:30,,,,]R)))(-[:315,,,,]O(-[:30,,,,]N?(-[:330,,,,]H)))}
    \arrow{0}[,0]\+
    \ce{H_2O}
    }
  \schemestop 
\end{center}

and the output shows

Answer 1

\usepackage{chemfig} 

\begin{document}
\schemestart[][184]
\subscheme
{
  \setatomsep{2.5em}
  \chemfig{Me-OH}
  \+
  \chemfig{C(=[:150]O)(-[:30]R)(-[:270,,,,]N(-[:330,,,,]H)(-[:210,,,,]{OH}))}
  \arrow(.mid east--.mid west)
}
\subscheme
{
  \chemfig{Me(-[:45,,,,<-]O(=[:330,,,,]C?(-[:30,,,,]R)))(-[:315,,,,]O(-[:30,,,,]N?(-[:330,,,,]H)))}
  \+
  \chemfig{H_2O}
}
\schemestop
\end{document}

Answer 2

1. place the \arrow{0}[,0] after \+ instead of before.
2. use a ring to build the molecule.

\documentclass{article}
\usepackage{chemfig}

\begin{document}

\begin{center}
  \schemestart
    \setatomsep{2.5em}
    \chemfig{Me-OH}
    \+
    \arrow{0}[,0]
    \chemfig{HO-[:30]N(-[:-30]H)-[:90]C(-[:30]R)=[:150]O}
    \arrow
    \chemfig{[:-36]Me*5(-O-N(-H)-C(-R)=O-[,,,,->])}
    \arrow{0}[,0]
    \+
    \chemfig{H_2O}
  \schemestop
\end{center}

\end{document}