The current study is focused on newly developed phenylpiperazine derivatives of aromatic methylhydantoin differing in mutual positions of methyl and phenyl moieties. The new compounds were synthesized using Bucherer-Bergs reaction, two-phase alkylation, Mitsunobu reaction and/or an alkylation under microwave irradiation. The compounds developed were assessed on their affinity for serotoninergic receptors 5-HT1A, 5-HT6, 5-HT7 and α1-ARs in radioligand binding assays. Selected compounds were tested on their inhibitory effect at human 5-HT3A expressed in Xenopus Oocytes as well as on their activity at α1-adrenoceptor subtypes in functional and electrophysiological bioassays, respectively. Most of investigated compounds exhibited affinities for α1-ARs, 5-HT1A, 5-HT7 (Ki ∼ 0.8-353 nM) significantly higher than those for 5-HT6 receptors. Very weak inhibitory effect at 5-HT3A accompanied with high activity at α1D-AR subtypes were observed for selected representative compounds. Among the current series, particularly 5-(4-fluorophenyl)-3-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-5-methylimidazolidine-2,4-dione hydrochloride (25a) displayed the highest 5-HT7 affinity with Ki = 3 nM and selectivity with 40-3600 fold towards 5-HT1A, 5-HT6, and α1-ARs.