Nicotinamide vitamin drugs

Drugs that are believed to be transported by this mechanism include phenytoin, methyldopa, nicotinamide, vitamin B12, 5-fluorouracil and thiamine. 

A TLC method was developed for the estimation of nieotinie aeid and nicotinamide (Fignre 10.7) in phatmacentical preparations containing other vitamins, enzymes, herbs, and drugs, etc. [16]. The percentage recoveries for nicotinic acid and nicotinamide were 100.1 + 1.9 and 100.2 1.5, respectively, with this system. Each alcohol extract of samples or standard was pnt on sihca gel TLC plates, which were developed with distilled water. Each silica gel spot visualized under UV lamp was collected and extracted with 0.1 mol/1 HCl. The optical density of each clear extract was measured at 262 run. 

The alkaloids are also relevant to drug design. Alkaloids are complex heterocyclic compounds that contain nitrogen and thus have base-like (hence the term alkaloid ) properties they are extremely structurally diverse. Nicotine is one of the simplest alkaloids. Oxidation of nicotine produces nicotinic acid, a vitamin that is incorporated into the important coenzyme nicotinamide adenine dinucleotide, commonly referred to as NAD" (oxidized form). The neurotransmitter serotonin is an alkaloid containing the aromatic indole ring system. 

A similar high-pH buffer has been used [7] in forensic studies to quantify and identify over lOO acidic drugs. Acidic vitamins can be separated [14] using high-pH buffers. However, resolution of neutral vitamins such as nicotinamide require the use of a chromatographic CE method 114]. 

Nicotinic acid (niacin) was first shown to lower serum cholesterol levels over 40 years ago (1955). This activity is not related to its vitamin functions (nicotinamide does not share its action). At daily doses of 3 g niacin s hypocholesterolemic effects are about equivalent to clofibrate. In addition to lowering triglycerides, it can also raise HDL levels. Unfortunately, at these high doses nicotinic acid can produce intense flushes and itching, resulting in poor patient compliance. Circumventing the problem with potential pro-drugs such as nicotinyl alcohol, fructose tetranicotinate, and others were not very successful. 

Alpha-picoline (2-picoline 2-methylpryridine) is used for the production of 2-vinylpyridine, which, when copolymerized with butadiene and styrene, produces a product that can be used as a latex adhesive which is used in the manufacture of car tires. Other uses are in the preparation of 2-beta-methoxyethyl-pyridine (known as promintic, an anthelmintic for cattle) and in the synthesis of a 2-picoline quaternary compound (amprolium), which is used against coccidiosis in young poultry. Beta-picoline (3-picoline 3-methylpryridine) can be oxidized to nicotinic acid, which, with the amide form (nicotinamide), belongs to the vitamin B complex both products are widely used to fortify human and animal diets. Gama-picoline (4-picoline 4-methylpyridine) is an intermediate in the manufecture of isonicotinic acid hydra-zide (isoniazide), which is a tuberculostatic drug. 2,6-Lutidine (2,6-dimethylpyridine) can be converted to dipicolinic add, which is used as a stabilizer for hydrogen peroxide and peracetic acid. 

Nicotinamide, or vitamin B3, characterized by a low toxicity, has been proven to solubilize a number of drugs, such as, for example, riboflavin (35) and nifedipine (36). A 36-fold increase of the solubility of riboflavin, which has a multi-aromatic ring system, at nicotinamide concentrations of about 2M, has been observed (35). It has been shown that complexation occurs between the riboflavin and the hydrotropic agents cytosine and caffeine, respectively (35). However, in the case of nicotinamide, no evidence for complexation between riboflavin and nicotinamide. 

Vitamin Bi (thiamine), B2 (riboflavin). Be (pyridoxine), B12 (cyanocobalamine), C (ascorbic acid), E (tocopherols), folic acid, pantothenic acid, K, K2, K3 (menadione), PP factor (nicotinamide), biotin Benzimidazole drugs, bromoisovalerylurea, cardiazol, chlorhexidine, dicoumarol, dulcin, isoniazid, 2-nitrofuran derivatives, parabens (4-hydroxybenzoic acid esters), phenacetin, phenylbutazone (and its metabolite oxyphenbutazone), propipocaine, quercetin, rutin, thiomersal (sodium ethylmercurithiosalicylate)... 

As in the case of FAB-MS, the use of surfactants such as cetyltrimethylammonium bromide (CTAB) can be used to substantially or even completely suppress the matrix-related ion background [81]. Use of the CTAB surfactant also resulted in an improved mass resolution for low-molecular-weight molecules including amino acids, peptides, drugs, and cyclodextrins. This technique has been used successfully for the analysis of caffeine, and the vitamins riboflavin, nicotinamide and pyridoxine in various energy drinks [82]. 

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