The idea of concession or opposition is often expressed by the participle alone ( cross2066) or by the participle with καίπερ or καὶ ταῦτα ( cross2083). The negative is οὐ. In negative concessive sentences we find also the participle with οὐδέ (μηδέ), οὐδέ (μηδέ) περ.
οὐδὲ πεπονθὼς κακῶς ἐχθρὸν εἶναί μοι τοῦτον ὁμολογῶ
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].