For many drugs, metabolism occurs in 2 phases. Phase I reactions involve formation of a new or modified functional group or cleavage (oxidation, reduction, hydrolysis); these reactions are nonsynthetic.
Use a capital letter for the first letter in the name when a noun is part of a name such as Calhoun High School. Use a capital letter in the case of a proper noun and in words that come from that proper noun. Examples: Texas and Texan. Use capital letters when naming religions, gods and any language.
It may be acceptable to drop capital letters when writing casually to friends but if you are writing anything more formal then you need to use capital letters correctly. This page lists the rules, and provides examples of when to use (and when not to use) capital letters in English writing.