How to remove specific special characters in R

Question

I have some sentences like this one.

c = \"In Acid-base reaction (page[4]), why does it create water and not H+?\" 

I want to remove all sp

Answer 1

gsub("[^[:alnum:][:blank:]+?&/\\-]", "", c)
# [1] "In Acid-base reaction page4 why does it create water and not H+?"