Well usually many people in Russia go abroad ( Milan, for example) to shop - especially for clothing items. Usually its cheaper there... But I am sure there are nice stores there in Moscow worth visiting anyways. Sorry I cant be more of a help, just google may be ? Found this link, may be it will help a bit.
If someone still interested in Moscow shopping I can give some advises.
As for me, I almost always choose TSUM when it comes to designer brands. Lots of people say it's too expensive and it'd better go abroad to shop, but I've never been the global-shopping person. I mean, I don't renew my wardrobe in full for the every new season. Just a couple of items quarterly - shoes in particular 'cause you should never economize on shoes, you know.
UK Style - 17, Nikitsky blvd
Alexander Boyd, A.P.C., Aquascutum, Barbour, Boudicca, B Store, D.S.Dundee, Fred Perry, Gloverall, Hackett, Jonathan Saunders, Margaret Howell, Markus Lupfer, Mary Katrantzou, Opening Ceremony, Our Legacy, Peter Jensen, Preen, Pretty Green, Pringle of Scotland, Richard James, Richard Nicoll, Rodebjer, Sophie Hulme, Stylein… http://www.ukstyle.ru/
Kuznetsky Most 20 - 20, Kuznetsky Most
Petrovsky Passage department store - 10, Petrovka street
here you can find: Jean Paul Gaultier, Kenzo, Moschino, Iceberg, Etro, Antonio Marras, Max Mara, Alberta Ferretti http://www.bosco.ru/articoli/passaj/
Prada, Yves Saint Laurent, Ralph Lauren, Roberto Cavalli