Avec l'extension `hyphenat` :
\documentclass[secnumdepth=subsubsection,12pt,space=onehalf,fncychap=Bjornstrup,nomakeabstract]{yathesis}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{kpfonts}
\usepackage{booktabs}
\usepackage{pdfpages}
\usepackage{siunitx}
\usepackage{pgfplots}
\usepackage{floatrow}
\usepackage{caption}
\usepackage{graphicx}
\usepackage{listings}
\usepackage{microtype}
\usepackage{subfig}
\usepackage{varioref}
\usepackage{multirow}
\usepackage{array}
\usepackage{chemformula}
\usepackage{xcolor}
\usepackage[xindy,quiet]{imakeidx}
\usepackage[autostyle]{csquotes}
\usepackage[backend=biber,sorting=none,style=numeric-comp]{biblatex}
\usepackage{hyphenat}
\usepackage{hyperref}
\usepackage[xindy,acronyms,symbols,nonumberlist]{glossaries}
\begin{document}
\mainmatter
\chapter{Introduction}
\subsection{(2S,3S)\hyp{}1\hyp{}azido\hyp{}4\hyp{}((dimethoxyphosphoryl)oxy)\hyp{}3\hyp{}((4\hyp{}methoxybenzyl)oxy)butan\hyp{}2\hyp{}yl stearate (10)}
BLABLA
\end{document}\end{document}
![alt text][1]
[1]: https://texnique.fr/osqa/upfiles/Screen_Shot_2021-01-25_at_13.31.33.png
