Extensions.conf Globals within Globals

Asterisk Asterisk Support
1

Dear all, Can I do this?

[globals]
GROUP1=SIP/3333|&SIP/3334&SIP/3335
GROUP2=SIP/4442|&SIP/4441&SIP/4442
GROUP3=SIP/5553|&SIP/5550&SIP/5556

EMERGENCY=${GROUP1}&${GROUP2}&${GROUP3}|9999|30

If not, how can I do the equivalent?