Complex sentence: Parents and preservationists, lead by Selim Khan-Magomedov, managed to list the school on the national register of memorial buildings, thus it became the only listed postconstructivist building in Moscow.
Split into simpler sentences: Parents and preservationists, led by Selim Khan-Magomedov, managed to list the school on the national register of memorial buildings. Thus, it became the only listed postconstructivist building in Moscow.