There's a comma before the AS where it shouldn't be.
USE Master
GO
CREATE DATABASE AdventureWorks_snap021607 ON
(NAME = AdventureWorks_Data, FILENAME = 'C:\AdventureWorks_data_021607.ss' ),
(NAME = fg0103SALES , FILENAME = 'J:\AdventureWorks_FileGroups\FG0103SALES\0103SALES.ndf'),
(NAME = fg0406SALES , FILENAME = 'J:\AdventureWorks_FileGroups\FG0406SALES\0406SALES.ndf'),
(NAME = fg0708SALES , FILENAME = 'J:\AdventureWorks_FileGroups\FG0708SALES\0708SALES.ndf')
AS SNAPSHOT OF AdventureWorks
GO
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability