pattern question

Hi,
	I would like to restrict a string based on a pattern:
               (The string cannot have the set:    ?:,'<>/*\|= and " )
<xsd:element name="LayerName">
			<xsd:simpleType>
				<xsd:restriction base="xsd:string">
					<xsd:minLength value="1"/>
					<xsd:maxLength value="255"/>
					<xsd:pattern
value="[^?:,'/\\\*&quot;&gt;&lt;|=]"/>  <!--Need suggestion here -->
				</xsd:restriction>
			</xsd:simpleType>
</xsd:element>

	Thanks for any info.

Regards,
Shyam Arigapudi
www.eds.com
shyam@ugs.com