AA - please clarify why you want to do this. Why not go directly to the gmail link and bypass the above?
I suppose that you could read the URL content and look for the link that you are interested in, namely the one for Gmail, which will be of the format
<a class=gb1 href="https://mail.google.com/mail/?tab=wm">Gmail</a>
The code to extract the URL for Gmail would then be
url = 'http://www.google.com';
urlContent = urlread(url);
gmailIdx = regexpi(urlContent,'Gmail');
hrefIdx = regexpi(urlContent(1:gmailIdx),'href=');
gmailURL = urlContent(hrefIdx(end)+6:gmailIdx-3);
web(gmailURL);
Of course, the big assumption is that the format for the Gmail link is described as above.
