Theophylline structure

Foods derived from cocoa beans have been consumed by humans since at least 460 to 480 AD. The source of cocoa beans, the species Theobroma, contains a variety of biologically active components. These include the purine alkaloids theobromine, caffeine, and theophylline. Structurally, they are methylated xanthines and, thus, are often referred to as methylxanthines. Theobromine (3, 7-dimethylxanthine) is the predominant purine alkaloid in cocoa and chocolate. Caffeine (1, 3, 7-trimethylxanthine), the major purine alkaloid found in coffee and tea, is found in cocoa and chocolate at about one eighth the concentration of theobromine. Only trace amounts of theophylline (1, 3-dimethylxanthine) are detected in cocoa and chocolate products. 

Common Name Theophylline aminoisobutanol Bufylline Structural Formula o... 

Common Name 7-((3-3 -picolylaminoethyl)theophylline nicotinate Structural Formula ... 

Drug Release from PHEMA-l-PIB Networks. Amphiphilic networks due to their distinct microphase separated hydrophobic-hydrophilic domain structure posses potential for biomedical applications. Similar microphase separated materials such as poly(HEMA- -styrene-6-HEMA), poly(HEMA-6-dimethylsiloxane- -HEMA), and poly(HEMA-6-butadiene- -HEMA) triblock copolymers have demonstrated better antithromogenic properties to any of the respective homopolymers (5-S). Amphiphilic networks are speculated to demonstrate better biocompatibility than either PIB or PHEMA because of their hydrophilic-hydrophobic microdomain structure. These unique structures may also be useful as swellable drug delivery matrices for both hydrophilic and lipophilic drugs due to their amphiphilic nature. Preliminary experiments with theophylline as a model for a water soluble drug were conducted to determine the release characteristics of the system. Experiments with lipophilic drugs are the subject of ongoing research. 

Case study theophylline anhydrate and monohydrate The type of structural information that can be obtained from the study of the x-ray diffraction of single crystals will be illustrated through an exposition of studies conducted on the anhydrate and hydrate phases of theophylline (3,7-dihydro-l,3-dimethyl-LH-purine-2,6-dione). The unit cell parameters defining the two phases are fisted in Table 7.2, while the structure of this compound and a suitable atomic numbering system is located in Fig. 7.3. 

As discussed above, one obtains a large amount of structural information upon completion of the data analysis, which will be illustrated using the example of theophylline monohydrate [20]. Table 7.3 contains a summary of intramolecular distances involving the non-hydrogen atoms in the structure, while Table 7.4 shows the intramolecular... 

Fig. 7.3. Molecular structure and suitable atomic numbering system for theophylline.

In a further application of MI-SPE, theophylline could be separated from the structurally related caffeine by combining the specific extraction with pulsed elution, resulting in sharp baseline-separated peaks, which on the other hand was not possible when a theophylline imprinted polymer was used as stationary phase for HPLC. A detection limit of 120 ng mb1 was obtained, corresponding to a mass detection limit of only 2.4 ng [45]. This combination of techniques was also used for the determination of nicotine in tobacco. Nicotine is the main alkaloid in tobacco and is the focus of intensive HPLC or GC analyses due to its health risk to active and passive consumers. However, HPLC- and GC-techniques are time-consuming as well as expensive, due to the necessary pre-purification steps required because the sample matrices typically contain many other organic compounds besides nicotine. However, a simple pre-concentration step based on MI-SPE did allow faster determination of nicotine in tobacco samples. Mullett et al. obtained a detection limit of 1.8 jig ml 1 and a mass detection limit of 8.45 ng [95]. All these examples demonstrate the high potential of MI-SPE to become a broadly applicable sample pre-purification tool. 

Monodisperse microspheres imprinted with theophylline or 17 (3-estradiol were used in competitive radioimmunoassays showing the MIP s high selectivity for the template molecule. In this case the assay is based on the competition of the target molecule with its radioactively labeled analogue for a limited number of antibody binding sites [77,118]. Figure 15 demonstrates that displacing the radioactively marked theophylline from the imprinted polymer was only possible with theophylline as competitor. Structurally related molecules showed effects solely at elevated concentrations [77]. 

Figure 6.2. Chemical structure of 8-[3-(7-/)-galactosylcoumarin-3-carboxyamido )propyl ] theophylline (B) used in the homogeneous substrate-labeled fluorescent immunoassay for theophylline (A). (Reprinted from Ref. 3, with permission from the American Association for Clinical Chemistry.)...

Theophylline (Fig. 20) is structurally very similar to caffeine and present at a low concentration in tea. It is also known as dimethyl xanthine. It is used for the treatments of asthma and COPD, for more than 50 years despite its many side effects. The mechanism of beneficial effect of theophylline is through HD AC activation. 

After the nucleic acid purines adenine and guanine, the next most prominent purine in our everyday lives is probably caffeine. Caffeine, in the form of beverages such as tea, coffee, and cola, is one of the most widely consumed and socially accepted natural stimulants. Closely related structurally are theobromine and theophylline. Theobromine is a major constituent of cocoa, and related chocolate products. Caffeine is also used medicinally,... 

The mechanism of action of theophylline as a broncholytic is unknown. However, some hypotheses are based on its structural similarity to adenosine and 3X5i-cyclic adenosinemonophosphate. 

In this section a variety of analytical separations reported in the literature are reviewed to show the wide structural diversity of eluite which can be separated by RPC and to assist the reader in becoming similar with the use of this fluid chromatographic technique. The descriptions are ar-ranged according to the matrix in which an analyte is found or the area of - h istry in which the samples are generally encountered. Thus theophylline, for example, is regarded as a nucleotide and, for the most part, its analysis in food samples is found with appropriate cross references. On the other hand, the separations of pharmaceuticals found in serum, urine, and pharmaceutical samples are cited separately. It is hoped that this method of classification may serve the purposes of those wh e analytical interests are incidental to their primary research pursuits. 

Ciprofloxacin (Cipro, Cipro XR, Proquin XR) [Antibiotic/ Fluoroquinolone] Uses Rx lower resp tract, sinuses, skin skin structure, bone/joints, urinary tract Infxns including prostatitis Action Quinolone antibiotic DNA gyrase Dose Adults. 250-750 mg PO ql2h XR 500-1000 mg PO q24h or 200-400 mg IV ql2h in renal impair Caution [C, /-] Children <18 y Contra Component sensitivity Disp Tabs, susp, inj SE Restlessness, N/V/D, rash, ruptured tendons, T LFTs Interactions T Effects Wf probenecid T effects OF diazepam, theophylline, caffeine, metoprolol, propranolol, phenytoin, warfarin effects W/ antacids, didanosine, Fe salts. Mg, sucralfate, Na bicarbonate,... 

A new purine derivative, 13-dimethylguanine, has been isolated from the ascidian Botrylloides leachi. Its structure has been elucidated by analysis of spectroscopic data by comparison with the regioisomer 13-dimethylisoguanine and by hydrolysis to theophylline <99MI638>. 

The purine ring-numbering scheme, 1, and structures of some simple purines, viz. adenine 2, guanine 3, caffeine 4, theophylline 5, adenosine 6, 2 -deoxyadenosine 7, guanosine 8, 2 -deoxyguanosine 9, xanthine 10, and hypoxanthine 11, are shown. 

---