C3：另外一个产物

$结构式：$

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\usepackage{chemfig}
\begin{document}
\chemfig{
C
	(-[4,0.3]H_2)
	(-[,0.8]\fbox{P})
	(-[6,0.8]C
		(-[,0.8]COOH)
		(-[4,0.8]HO)
	)
}
\end{document}