More formal synonyms of "snob"
Solution 1:
For a noun, elitist might work.
Solution 2:
Class-conscious has the same meaning as snobbish in its original form, but hardly anyone could genuinely be accused of class-consciousness nowadays. The commoner forms (based on riches, education or accent) don't really lend themselves to this formation; the closest I can think of is mindful of his income/background.