org-latex-regexps

org-latex-regexps is a variable defined in `org.el'.
Its value is

(("begin" "^[ 	]*\\(\\\\begin{\\([a-zA-Z0-9\\*]+\\)[^]+?\\\\end{\\2}\\)" 1 t)
 ("$1" "\\([^$]\\|^\\)\\(\\$[^ 	
\n,;.$]\\$\\)\\([- 	.,?;:'\")]\\|$\\)" 2 nil)
 ("$" "\\([^$]\\|^\\)\\(\\(\\$\\([^ 	
\n,;.$][^$\n
]*?\\(\n[^$\n
]*?\\)\\{0,2\\}[^ 	
\n,.$]\\)\\$\\)\\)\\([- 	.,?;:'\")]\\|$\\)" 2 nil)
 ("\\(" "\\\\([^]*?\\\\)" 0 nil)
 ("\\[" "\\\\\\[[^]*?\\\\\\]" 0 nil)
 ("$$" "\\$\\$[^]*?\\$\\$" 0 nil))

Documentation:
Regular expressions for matching embedded LaTeX.