'(' and ')' are special characters. They are used grouping commands like:

>(md x && cd x) || (echo "Couldn't create x" & exit)
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The rules for how cmd.exe treats quotes (usefully provided by help cmd), are as follows:

If /C or /K is specified, then the remainder of the command line after
the switch is processed as a command line, where the following logic i
+s
used to process quote (") characters:

    1.  If all of the following conditions are met, then quote charact
+ers
        on the command line are preserved:

        - no /S switch
        - exactly two quote characters
        - no special characters between the two quote characters,
          where special is one of: &<>()@^|
        - there are one or more whitespace characters between the
          two quote characters
        - the string between the two quote characters is the name
          of an executable file.

    2.  Otherwise, old behavior is to see if the first character is
        a quote character and if so, strip the leading character and
        remove the last quote character on the command line, preservin
+g
        any text after the last quote character.

...
The special characters that require quotes are:
     <space>
     &()[]{}^=;!'+,`~
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