red-brown vs mahogany-red

red-brown and mahogany-red both are adjectives.

Word	Noun	Adjective	Verb	Adverb
red-brown	No	Yes	No	No
mahogany-red	No	Yes	No	No

As adjectives, red-brown and mahogany-red are synonyms defined as:

Other synonyms of red-brown include reddish-brown.

red-brown (adjective)	mahogany-red (adjective)
of brown tinged with red	of brown tinged with red