Loratadine, structure

Lithocholic acid, structure of, 1082 Locant, IUPAC naming and, 87 Lone-pair electrons, 9 Loratadine, structure of, 206 Lotaustralin. structure of. 766 Low -density polyethylene, synthesis of, 1210... 

Antihistamines are drags used to counteract the effects of histamine on body organs and structures. Examples of antihistamines include diphenhydramine (Benadryl), loratadine (Claritin), fexofenadine (Allegra), and cetirizine (Zyrtec). A new antihistamine, deslorata-dine (Clarinex), is die active metabolite of loratadine and is intended to eventually replace loratadine (Claritin). Topical corticosteroid nasal sprays such as fluticasone propionate (Flonase) or triamcinolone ace-tonide (Nasacort AQ) are also used for nasal allergy symptoms. See Chapter 56 for more information on die topical corticosteroids. 

Second-generation antihistamines Flypersensitivity to specific or structurally related antihistamines. Desloratadine is contraindicated in those who are hypersensitive to loratadine. Cetirizine is contraindicated in those who are hypersensitive to hydroxyzine. 

In this chapter, the utility of LC-electrospray ionization (ESI)-MS, LC-ESI-MS/MS, LC-APCI-MS, LC-APCI-MS/MS, and HDX-LC-MS for structural identification of metabolites and derivatives of loratadine and desloratadine is discussed. 

Although the generic companies were interested in manufacturing loratadine, the federal court hearing the case construed claims 1 and 3 to cover DCL in any form (both parties agreed to this constmction). This is because claims 1 and 3 simply do not provide any limitation as to the purity of DCL nor the quantity required for infringement of the claim. However, you may have noticed that the structure... 

An inspection of the structures listed (this list is not comprehensive) makes it clear that the analogue principle has also been applied for the nonsedating compounds. Most of these compounds have been identified by chance. For example, loratadine (Fig. 18.15) - a derivative of another highly sedating antihistamine, aza-... 

Loratadine is structurally related to the antihistamines aza-tadine and cyproheptadine. It differs from azatadinc, in that a neutral caAamate group has replaced the ba.sic tertiary... 

Loratadine, marketed as an antiallergy medication under the name Claritin, has four rings, eight double bonds, and the formula C22H7CIN2O2. How many hydrogens does loratadine have (Calculate your answer don t count hydrogens in the structure.)... 

Second-generation compounds have been developed in order to minimize the sedative effects of the earlier compounds, which is achieved by modifying structures in such a way as to limit access to the CNS. They include alkylamines (e.g. acrivastine) and piperazines (e.g. cetirizine) and piperidines (e.g. astemizole, levocabastine. loratadine and terfenadine). 

In the discovery phase, metabolite identification is usually performed with a combination of in vitro and in vivo experiments using samples from different species in order to compare metabolite exposures. The structural identification of major circulating metabolites formed in nonclinical animal models as well as the metabolites formed in human in vitro systems is needed for the metabolites to be synthesized and their pharmacological activities and/or toxicological implications to be determined [25], In addition, metabolite identification can lead to the discovery of candidates with satisfactory clearance/PK properties and/or improved safety profile. Following are some examples of metabolites that were later developed as drugs desloratadine from loratadine, acetaminophen from phenacetin, morphine from codeine, minoxidil sulfate from minoxidil, fexofenadine from terfenadine, and oxazepam from diazepam. 

A. blocker antihistamines are structurally related to histamine and antagonize the effects of histamine on H., receptor sites. They possess anticholinergic effects (except the nonsedating agents astemizole, azelastine, cetirizine, desloratadine, fexofenadine, loratadine, and terfenadine). They may also stimulate or depress the CNS, and some agents (eg, diphenhydramine) have local anesthetic and membrane-depressant effects in large doses. 

Chemical structures of loratadine, P-cyclodextrin (P-CD) and 2-hydroxypropyl-P-cydodextiin (HP-P-CD)... 

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