Fexofenadine hydrochloride

Biological target Fexofenadine is a racemic carboxylic analogue of terfenadine and a highly hydrophilic zwitterionic amino acid, which is a specific antagonist at Hi histamine receptors. 

Therapeutic profile The drug is a second-generation antihistamine, lacking sedative activity, for the treatment of allergic diseases, including allergic rhino-conjunctivitis, seasonal allergic rhinitis, urticaria and atopic dermatitis. 

Synthetic highlights Although not feasible from a cost-benefit point of view, racemic switch to the R(+) enantiomer is discussed. Retrosynthetic analysis of the fexofenadine molecule is presented together with some inventive synthetic steps employed. These include ZnBr2-catalyzed transposition (rearrangement) of a-haloketones to terminal carboxylic acids and microbial oxidation of the non-activated C-H bond. The concept of bioisosterism is exemplified by the silicon switch of fexofenadine to sila-fexofenadine. 

Fexofenadine hydrochloride (1, ( )-2-[4-]-lhydroxy-4-(hydroxydiphenylmethyl)-l-piperidino]butyl]phenyl]-2-methylpropanoic acid, Allegra ) is an antihistamine agent, acting as an Hi antagonist. 

It is clinically effective in the treatment of seasonal allergic rhinitis and chronic idiophatic urticaria and is not associated with adverse cardiac or cognitive/psycho-motor effects. These qualities have led to the ranking of fexofenadine in eighth place among the 200 best marketed drugs, and in 2007, it led to approximately 0.9 billion in sales. 

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C Hs 71-43-2) see Budipine Clotrimazole Fexofenadine hydrochloride Ibuprofen Phenylmercuric borate ... 

C H2 C103 76811-97-7) see Fexofenadine hydrochloride 4-(2-chloro-2-oxoethyl)-l-piperidinecarboxylic acid phe-nylmethyl ester... 

C4H5CIO 4023-34-1) see Buprenorphine Fexofenadine hydrochloride Naltrexone Prazepam cyclopropanecarboxylic acid ethyl ester (C(,H o02 4606-07-9) see Pimozide... 

G16H20O3 169280-10-8) see Fexofenadine hydrochloride ethyl l-cyclopropyl-6,7-difluoro-S-methyl-l, 4-dihydro-4-oxoquinoline-3-carboxylate... 

C32H37NO4 76811-98-8) see Fexofenadine hydrochloride 4-[4-[4-(hydroxydiphenylmethyl)-l-piperidinyl]-l-oxo-butyl]-a,a-dimcthylbenzeneacetic acid ethyl ester (C34H4[N04 76812-02-7) see Fexofenadine hydrochloride 3a-hydroxy-2p,16p-dipiperidino-5a-androstan-17-one (C2cjH4jN202 13522-14-0) see Pancuronium bromide Vecuronium bromide 9-hydroxyellipticine... 

Fexofenadine hydrochloride is rapidly absorbed into the body following oral administration, with Tmax occurring at approximately 1-3 hours post dose. It is 60-70% plasma protein bound. 

Common Name Fexofenadine hydrochloride Structural Formula ... 

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