Rewrite all root level pages using Regex

I'm looking to re-write all root level pages on my server bar a few. The code I currently have is as follows:

<rule name="front-end-global" stopProcessing="true">
<match url="^/([^/]+)?$" />
<action type="Rewrite" url="/y-essentialibiza-com/{R:1}" />
<conditions>
<add input="{REQUEST_FILENAME}" pattern="buy.asp" negate="true" />
<add input="{REQUEST_FILENAME}" pattern="buy-vip-submitted.asp" negate="true" />          
<add input="{REQUEST_FILENAME}" pattern="m-buy-mtl.asp" negate="true" />   
</conditions>
</rule>  

But this isn't working. I'd also like to negate certain folders but can't find a way to do this.

Apologies for the basic nature of this question. I'm new to Regex.

Thanks in Advance,

PJ