Number of compounds from the following which will not produce orange red precipitate with Benedict solution is _______
Glucose, maltose, sucrose, ribose, 2-deoxyribose, amylose, lactose

Benedict's solution tests for reducing sugars (those with free aldehyde or ketone groups that can reduce Cu²⁺).

Reducing sugars (give orange-red precipitate): Glucose, maltose, ribose, 2-deoxyribose, lactose

Non-reducing (do NOT give precipitate): Sucrose (glycosidic bond between reducing ends of both glucose and fructose) and amylose (polysaccharide, does not give positive Benedict's test)

Number of compounds not producing orange-red precipitate = 2