Rottapharm Biotech S.r.l.

Benedetta Buzzi

Lucio C Rovati

Gianfranco Caselli

Roberto Artusi

Luigi Piero Stasi

Stefano Mandelli

Tiziana Piepoli

Fabrizio Colace

Manuela Borriello

Filippo Magaraci

Clara Bovino

Laura Mennuni

Lucio Claudio Rovati

The present invention provides a process for preparing (R)-6-(tert-butoxycarbonyl)-6-azaspiro[2.5]octane-5-carboxylic acid (SM1), said process comprising the step of: iv) converting a compound of formula (VII) into a compound of formula (VIII) using a Wittig reagent in a suitable solvent; v) reacting through the Makosza reaction the compound of Formula (VIII) using bromoform and a suitable base to obtain cyclopropane compound of Formula (IX); and vi) removing bromine atoms in the presence of a reducing agent and a base in an alcoholic solvent thus obtaining (SM1). The invention relates also to a process for the conversion of the compound (SM1) for preparing (R)-4-(1-(6-(4-(trifluoromethyl)benzyl)-6-azaspiro[2.5]octane-5-carboxamido)cyclopropyl) benzoic acid (IV) or a salt thereof. The salt is preferably the sodium salt, more preferably the polymorphic form A of sodium (R)-4-(1-(6-(4-(trifluoromethyl)benzyl)-6-azaspiro[2.5]octane-5-carboxamido)-cyclopropyl) benzoate characterized by a powder XRD spectrum with peaks at values of the angle 2θ+0.2° of 4.3, 5.0, 5.8, 6.4, 7.1, 8.3, 8.7, 12.8, 15.3, 15.9.

Process for the preparation of (R)-4-(1-(6-(4-(trifluoromethyl)benzyl)-6-azaspiro[2.5]octane-5-carboxamido)-cyclopropyl) benzoic acid or a salt thereof

The invention relates pyridine amide derivative of Formula (I) or a pharmaceutically acceptable salt thereof, wherein Rand Rare independently hydrogen, linear o branched (C1-C3)alkyl or joined together they form a cyclopropyl ring; R is independently selected from the group consisting of halogens and trifluoromethyl and p is 1, 2 or 3; A is C or N; E is a group of formula (B) or (C), wherein B is C(O)OH, C(O)O(C1-C3)alkyl, and C is selected from the group consisting of formula (I) m is 1,2 or 3, n is 0 or 1, W is &#x2014;O&#x2014;, &#x2014;O(C1-C3 alkyl)-; &#x2014;(C1-C3 alkyl)O&#x2014;; &#x2014;C(O)&#x2014;; &#x2014;C(&#x2550;N&#x2014;O(C1-C3 alkyl))-; &#x2014;NH&#x2014; or &#x2014;NH(C1-C3alkyl)-; Ar is phenyl, optionally substituted with one or more substituents selected from the group consisting of halogen, trifluoromethyl, trifluoromethoxy, methyl, &#x2014;NH(C1-C3alkyl)-; &#x2014;N(C1-C3alkyl)(C1-C3alkyl)-, a from 5 to 7 membered heterocyclic ring containing one nitrogen atom which is covalently bonded to Ar and optionally containing one or two heteroatoms selected from N, O and S; and a 5- or 6-membered heteroaromatic ring containing 1 to 3 heteroatoms selected from S, O e N, such heteroaromatic ring being substituted with one or two substituents selected from the group consisting of (C1-C3)alkyl, (C3-C5)cycloalkyloxy, (C1-C3)alkylcarbonyl. The compounds of the invention could be used for manufacturing a medicament for the treatment of pathologies which require the use of an antagonist of the EP4 receptor, such as the treatment of acute and chronic pain, inflammatory pain, osteoarthritis, inflammation-associated disorder as arthritis, rheumatoid arthritis, cancer, endometriosis and migraine. 

Pyridine amide derivatives as EP4 receptor antagonists

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Meda, Italy

Benedetta Buzzi