Hi Sunitha,
Converting LaTeX to XML can be a tricky proposition with all the macro packages, but below are two popular applications for the job:
http://dlmf.nist.gov/LaTeXML/http://tug.org/applications/tex4ht/mn.htmlIf anyone has experience with either packages, I'd love to hear your thoughts.
Once they are in XML you can easily import the file into XMetaL. If you need a plug-in to work with the MathML, please come see us:
http://www.dessci.com/en/products/mathflow/mf_for_xmetal.htmBest wishes,
Autumn Cuellar
Associate Product Manager, Design Science.