name = c("company", "deriv.x", "isConfirmed.y")
new.name = gsub(".x$|.y$", "", name)
new.name
[1] "compa"       "deriv"       "isConfirmed"

remove = c(".x", ".y")
replace(name, name %in% remove, "")
[1] "company"    "deriv.x"    "isConfirmed.y"

(.+?)(?:..+)?

gsub("(.+?)(?:\..+)?", "\1", "deriv.x")

name = c("company", "deriv.x", "isConfirmed.y")
new.name = gsub("\.x$|\.y$", "", name)
new.name

[1] "company"     "deriv"       "isConfirmed"