private static readonly Regex specialCharactersPattern
        = new Regex("[\\[*($%&)<>!?\\/\"{}\\s+-='@~`#\\\\:;^\\]]", 
            RegexOptions.Compiled);

    private static readonly Regex encodedCharactersPattern
        = new Regex("_x00(\\d{2})_", RegexOptions.Compiled);

    /// <summary>
    /// Normalizes the name of the SharePoint property name.
    /// </summary>
    /// <param name="key">The "human readable" key/property name.</param>
    /// <returns>
    /// The string with hex representation in place of special ASCII
    /// characters.
    /// </returns>
    private static string NormalizeSharePointPropertyName(string key) {
        return specialCharactersPattern.Replace(key, ReplaceSpecialCharacter);
    }

    /// <summary>
    /// Custom match evaluator to replace special characters within the input
    /// string.
    /// </summary>
    /// <param name="match">The pattern match.</param>
    /// <returns>The formatted version of the string.</returns>
    private static string ReplaceSpecialCharacter(Match match) {
        string replacement = string.Format("_x00{0}_",
            Uri.HexEscape(match.Value[0]).TrimStart('%'));

        return replacement;
    }

    /// <summary>
    /// Denormalizes the name of the SharePoint property.
    /// </summary>
    /// <param name="key">The normalized key/property name (static name).</param>
    /// <returns>
    /// The denormalized form of the input string ("human readable"
    /// with hex patterns replaced).
    /// </returns>
    private static string DenormalizeSharePointPropertyName(string key) {
        return encodedCharactersPattern.Replace(key, DecodeSpecialCharacter);
    }

    /// <summary>
    /// Custom match evaluator to replace the hex characters with special characters.
    /// </summary>
    /// <param name="match">The pattern match.</param>
    /// <returns>The ASCII format of the special character encoded in hex.</returns>
    private static string DecodeSpecialCharacter(Match match) {
        int start = 0;

        string replacement =
            Convert.ToString(
                Uri.HexUnescape(Convert.ToString(match.Value[0]), ref start)
            );

        return replacement;
    }