Ritalin - Methylphenidate hydrochloride

Ritalin (Methylphenidate hydrochloride). Novartis Pharmaceuticals UK Ltd UK Summary of product characteristics, June 2007. 

Chan, Y.P., Swanson, J.M., Soldin, S.S., Thiessen, JJ-, and Macleod, S.M. (1983) Methylphenidate hydrochloride given with or before breakfast II. Effects on plasma concentration of methylphenidate and ritalinic acid. Pediatrics 72 56-59. 

Central Nervous System Stimulants Central nervous system stimulants include agents such as the amphetamines (Dexedrine) and methylphenidate hydrochloride (Ritalin), used to elevate mood, suppress appetite, and control hyperkinetic disorders in children. Other examples include the illegal drugs methamphet-amine and cocaine. The mechanism of action of these drugs is to augment actions of the adrenergic nervous system. 

Methylphenidate Hydrochloride, USP. Becau.se methylphenidate (Ritalin) has two asymmetric centers, there arc four possible isomers. The threo racemate is the inar-... 

S-methylhomocy teine methionine, methylisogenistin genistein. /V-methylmescaline mescaline, methylmorphine codeine, a-methy I noradrenaline levonordefrin. methyl pentynol (ban. inn] is an acetylenic carbinol. with HYPNOTIC and SEDATIVE properties. It has been used in the treatment of insomnia and as an anxiolytic. methyl-PGEj arbaprostil. methylphenidate [ban, inn] (methylphenidate hydrochloride [jan, usan] Ritalin ) is a CNS STIMULANT and dopamine (re) UPTAKE INHIBITOR. It is used in the treatment of attention-deficit hyperactivity disorder in children, methylphenidate hydrochloride methylphenidate. 

CCRIS 6258 Centedrin Centedrine EINECS 206-065-3 Meridil hydrochloride Metadate CD Methylin Methylphenidate hydrochloride Methylphenidylacetate hydrochloride Metilfenidat hydrochloride NSC 169868 Ritalin Ritalin hydrochloride. CNS, psychomotor stimulant. Crystals mp = 224-226° soluble in H2O, EtOH, CHCI3 LD50 (mus orl) = 190 mg/kg. CIba-Geigy Corp. 

Methylphenidate hydrochloride Methyl a-phenyl-a-(2-piperidyl) acetate hydrochloride U.S.P. Ritalin Hydrochloride (Ciba-Geigy)... 

Ritalin capsules when these are to be prepared from methylphenidate hydrochloride it is simple, since the strength of Ritalin tablets relates to methylphenidate hydrochloride. 

A research group at Novartis also utilized Evans aldol reaction in a straightforward synthesis of (/ ,/ )-methylphenidate hydrochloride (ritalin hydrochloride), the drug well known for the treatment of attention deficit hyperactivity disorder (AD HD). In the key step, displayed in Scheme 4.58, N-acylated oxazolidinone 249, the standard boron enolate addition to 5-chloropentanal, yielded 250 as a single diastereomer that was transformed in several steps into Ritalin hydrochloride. In the aldol step, temperatures lower than -20 °C could be avoided, what makes the procedure applicable in a manufacturing scale [130]. 

Methylphenidate hydrochloride (Ritalin and Concerta [Novartis, Basel, Switzerland]) (11, Scheme 2.1) is a mild nervous system stimulant that is primarily prescribed for treatment of attention deficit hyperactivity disorder in children. Although it is marketed in its racemic form, it has been reported that the (+) enantiomer is 5 to 38 times more active than its racemate.Although previous syntheses of (+)-methylphenidate involved classic resolution, researchers at Novartis reported an enantioselective synthesis of (+)-methylphenidate in 1997. As depicted in Scheme 2.1, the synthesis began with a diastereoselective... 

Clonidine hydrochloride (Catapres), carbamazepine (Tegretol), and methylphenidate (Ritalin) are occasionally useful in intractable cases of migraine. Cyproheptadine (Periactin) may be effective in adults with migraine it is of considerable importance in the treatment of childhood migraine, and many consider it to be the drug of first choice. Dosages range from 4 to 3 mg, three to four times a day, in adults and 4 mg, two to three times a day, in children. 

Demerol), cocaine, oxycodone (Percodan), Anileridine (Leritine), and oxymorphone (Numorphan). Also in Schedule II are amphetamine (Benzedrine, Dexedrine), methamphetamine (Desoxyn), phenmetrazine (Preludin), methylphenidate (Ritalin), amobarbital, pentobarbital, secobarbital, methaqualone, etorphine hydrochloride, diphenoxylate, and phencyclidine. 

Ritalin pills contain the hydrochloride salt methylphenidate. When the salt comes in contact with water, it yields hydrochloric acid. This is not a problem when the pills are taken orally, because hydrochloric acid is one of the digestive acids present in the stomach. When the drug is snorted, however, the corrosive acid can burn the tissues in nasal passages and cause open sores, nosebleeds, and even deterioration of the nasal cartilage. 

An example from our own laboratory is the methylphenidate bioanalyti-cal chiral LC-MS/MS assay in support of toxicokinetics (TK) and PK studies (vide infra). Attention-deflcit hyperactivity disorder (ADHD) is a recognized medical problem characterized by symptoms of inattention, hyperactivity, and impulsivity. Methylphenidate (MPH Ritalin methyl-alpha-phenyl-2-piperid-inacetate hydrochloride) is prescribed for the treatment of ADHD. MPH has two chiral centers yielding enantiomers with distinct pharmacokinetic and pharmacodynamic properties in humans. It is known that the t/-threo [2R,2 R]-MPH (i.e., (-i-)-threo) exhibits greater pharmacological activity than the... 

An efficient and large scale resolution of methylphenidate (ritalin hydrochloride)using dibenzoyl-tartaric acid has been described (61). Ritalin is marketed for the treatment of children with attention deficient disorder (ADHD). Methylphenidate has two chiral centers and originally was marketed as a mixture of two racemates, 20% OL-threo (29, 30) and 80%DL-erythro (31, 32) (see Fig. 18.12 for the structures of all four isomers). As introduced previously, the erythro-isomer is defined as the case when the main chain of a molecule (drawn vertically in a Fischer projection)has identical or similar substituents at two adjacent non-identical chiral centers on the same side of the chain, whereas the threo isomer has... 

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