Regular expression

[=?Utf-8?B?Q2hyaXN0aWFuIEhhdmVs?=]

Hi,

I have a string that looks like following:

<arguments>
<item name=\"FIRSTNAM E\" value=\"' < & >\"/>
<item name=\"NAME\" value=\"MyName\ "/>
</arguments>"

In this string I want to replace < with <
How can I do this this using recular expression?
Christian