B. BELLEAU, P. MORGAN: "Clastic binding on the opiate receptor", J. MED. CHEM., vol. 17, no. 8, 1974, pages 908-909, XP002553111, (B1)

FOSTER A B: "Deuterium isotope effects in the metabolism of drugs and xenobiotics: implications for drug design", ADVANCES IN DRUG RESEARCH, ACADEMIC PRESS, LONDON, GB, vol. 14, 1 January 1985 (1985-01-01), pages 1-40, XP009086953, ISSN: 0065-2490 (B1)

HEDVIG BÖLCSKEI, MARIANNA MAK, FERENCZ DRAVECZ, GYÖRGY DOMANI: "Synthesis of deuterated dextrometorphan derivatives", ARKIVOC, vol. 2008, no. 3, 4 April 2008 (2008-04-04), pages 182-193, XP002553112, Gainesville, FL, US (B1)

WO-A-95/26325 (B1)

MARTIN I BLAKE ET AL: "Studies with Deuterated drugs", 1 March 1975 (1975-03-01), JOURNAL OF PHARMACEUTICAL SCIENCES, AMERICAN PHARMACEUTICAL ASSOCIATION, WASHINGTON, US, PAGE(S) 367 - 391, XP009090019, ISSN: 0022-3549 * page 368 - page 369 * (B1)

TORTELLA F C ET AL: "NOVEL ANTICONVULSANT ANALOGS OF DEXTROMETHORPHAN: IMPROVED EFFICACY, POTENCY, DURATION AND SIDE-EFFECT PROFILE", JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS, AMERICAN SOCIETY FOR PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS, US, vol. 268, no. 2, 1 January 1994 (1994-01-01), pages 727-733, XP009066525, ISSN: 0022-3565 (B1)

WO-A-2008/137474 (B1)

KUSHNER DJ ET AL: "Pharmacological uses and perspectives of heavy water and deuterated compounds", CANADIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY, OTTAWA, ONT, CA, vol. 77, no. 2, 1 February 1999 (1999-02-01), pages 79-88, XP009086918, (B1)