You either enclose with single quotes or escape with backtick. In this example i'm using an instance of the 'Windows Server' class from one of the default SCOM management packs. This class inherits the property 'IPAddress' from the base class 'Windows Computer'.
Here are the useable options for PowerShell:
#Get all available properties Get-SCOMClass -DisplayName "Windows Server" | Get-SCOMClassInstance | Get-Member ... [Microsoft.Windows.Computer].ActiveDirectoryObjectSid [Microsoft.Windows.Computer].ActiveDirectorySite [Microsoft.Windows.Computer].DNSName [Microsoft.Windows.Computer].DomainDnsName [Microsoft.Windows.Computer].ForestDnsName [Microsoft.Windows.Computer].HostServerName [Microsoft.Windows.Computer].IPAddress [Microsoft.Windows.Computer].IsVirtualMachine [Microsoft.Windows.Computer].LastInventoryDate [Microsoft.Windows.Computer].LogicalProcessors [Microsoft.Windows.Computer].NetbiosComputerName [Microsoft.Windows.Computer].NetbiosDomainName [Microsoft.Windows.Computer].NetworkName [Microsoft.Windows.Computer].OffsetInMinuteFromGreenwichTime [Microsoft.Windows.Computer].OrganizationalUnit [Microsoft.Windows.Computer].PhysicalProcessors [Microsoft.Windows.Computer].PrincipalName [Microsoft.Windows.Computer].VirtualMachineName ... # # Using a NoteProperty # ** Where-Object / ForEach-Object clause ** { $_.'[Microsoft.Windows.Computer].IPAddress'.Value } # ** Select-Object ** Select-Object ``[Microsoft.Windows.Computer`].IPAddress Select-Object *.IPAddress # ** Change column name or object property name ** # Looks like the syntax for Where-Object, but 'Value' subproperty is not specified! Select-Object @{Expression={$_.'[Microsoft.Windows.Computer].IPAddress'};Label="IP"}