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Reference 1H, 19F and 13C NMR, mass, IR and Raman spectra are provided to the open literature for the first time for the potent antifungal agent fluconazole, alpha-(2,4-difluorophenyl)-alpha-(1H-1,2,4-triazol-1-ylmethyl++ +)-1H-1,2, 4-triazole-1-ethanol. The 1H, 19F and 13C NMR spectra were analyzed in detail to attribute shifts, including 19F chemical shifts and C-F and F-F coupling constants. The EI mass spectrum, although rich in fragment ions, lacked a molecular ion. FAB and MS/MS experiments were undertaken in support of the structure in order to validate the EI spectrum as a reference mass spectrum. IR and Raman spectra are compared to show the complementary nature of their features and discussed in terms of principal group vibrations. NMR and vibrational data together with assignments are summarized in tabulated form for convenience of use. All these data are consistent with the structure of fluconazole.

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The dissolution of reference and archival samples of flurazepam dihydrochloride (2) was studied in DMSO-d6 and in D2O by 1H-, 13C- and 19F-NMR spectroscopy to identify and distinguish solvated species of the parent drug (2), the "benzophenone" (4) and glycine (5) hydrochloride degradation products. In DMSO-d6, for most samples, only the ring intact form (2) could be detected by 13C-NMR whereas the inherently greater sensitivity of 19F-NMR allowed detection of initial trace amounts (< 1%) of the open-ring form (3). 19F-NMR spectroscopy also afforded the best means of quantifying the various entities in solution, including the increase towards equilibrium levels of the open-ring entity and detection/quantitation of a new equilibrium species, possibly the cis/trans rotamer of the open-chain entity (3). Various chemical shifts for flurazepam dihydrochloride and USP flurazepam related reference standards C and F are reported for DMSO-d6 solutions. The bases for 1H- and 19F-NMR assay of DMSO-d6 solutions of (2) for (4) are discussed with comparative data. The solvation characteristics of (2) in D2O at 0 and 27 degrees C were found to be too complex to follow by 13C-NMR; however, 19F-NMR studies at these temperatures permitted one to clearly discern that no additional formation of entity (4) occurred beyond whatever initial levels were present in degraded samples while the open-ring entity (3) was observed to increase to an equilibrium level of 56% over 24 h at 27 degrees C. Dissolution in D2O at either 0 or 27 degrees C does not contribute to solvolytic degradation of (2) to (4) over 24 h.

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Fourier transform (FT) Raman and IR spectra of flurazepam base and the mono- and dihydrochloride salts have been recorded. The parent compounds is 7-chloro-1-[2-(diethylamino)ethyl]-5-(2-fluorophenyl)-1,3-dihydro-[2H]- 1,4-benzodiazepin-2-one and is closely related to diazepam. The spectra show characteristic features associated with both the diazepine ring and substituents. Very strong lines near 1615 cm-1 in the Raman spectra of the base and the monohydrochloride are assigned to the C = N stretch of the diazepine ring. The C = N group becomes a C = N+ group in the dihydrochloride and the frequency shifts to 1635 cm-1. A very strong absorption near 1680 cm-1 in the IR spectra of the three compounds is attributed to the C = O stretching mode. The hydrochlorides are characterized by very strong broad bands in the IR spectra between 2600 and 2200 cm-1. Various IR and Raman vibrational features serve to characterize and differentiate the salts from each other and the free base. Raman and IR spectra have also been recorded for the related compound desalkylflurazepam [7-chloro-5-(2-fluorophenyl)-1,3-dihydro-[2H]-1,4-benzodiazepin-2- one], in which a hydrogen atom replaces the (diethylamino)ethyl group at position 1 of the diazepine ring. Comparison of the spectra of this compound with those of flurazepam has enabled some vibrations of the (diethylamino)ethyl group to be identified.

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Archival samples of flurazepam monohydrochloride and "hydrochloride" (i.e., the dihydrochloride) were examined by Fourier transform infrared and Raman spectroscopy to determine evidence of degradation during storage for 13-15 years. No degradation of the three different batches of monohydrochloride salts was detected, but various degrees of degradation of the eight specimens of flurazepam hydrochloride diprotonated salts were indicated by enhanced intensities (IR 1635, 1509, 1226; Raman 1636, 1408, 1149 cm-1) and new features (IR 1742, 943, 755; Raman 1554, 837, 742 cm-1). All of these features, except the 1742 cm-1 IR band, were attributed to the presence of the hydrolysis product 5-chloro-2-[[2-(diethylamino)ethyl]amino]-2'-fluorobenzophenone hydrochloride whereas the 1742 cm-1 band was attributed to glycine hydrochloride, the other hydrolytic moiety. The flurazepam hydrochloride samples were also examined in deuterated dimethyl sulfoxide solution by proton nuclear magnetic resonance (1H-NMR) spectroscopy to verify the presence of the degradation products and to estimate the levels of degradation (approximately 3-36%) of the drug. IR and Raman spectra of the "benzophenone" hydrochloride in the "fingerprint" region are compared with two samples of flurazepam dihydrochloride (slightly and highly degraded) and their features discussed. Vibrational assignments are made and discussed for the observed IR and Raman wavenumbers for the "benzophenone" hydrochloride.

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Fourier transform-Raman and IR spectra of four compounds that are closely related to diazepam (Valium) have been recorded. The compounds, delorazepam, fludiazepam, flurazepam, and tetrazepam, are all 7-chloro-1,3-dihydro-[2H]-1,4-benzodiazepine -2-ones and differ from diazepam by the substituents at positions 1 and 5 of the diazepine ring. The spectra show characteristic features associated with both the diazepine ring and substituents. A strong line near 1610 cm-1 in the Raman spectra is assigned to the C = N stretch of the diazepine ring, and very strong IR absorption near 1690 cm-1 is attributed to the C = O stretching mode. Various IR and Raman vibrational features serve to characterize and differentiate these molecules. Evidence for intermolecular hydrogen bonding in one of the compounds (delorazepam) is presented.

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Anthraquinones and structurally related compounds were cytotoxic to mammalian cell lines using cloning efficiency and MTT reduction as endpoints. In V79 cells, the concentration of chemical causing 50% inhibition ranged from 0.21 to 21.6 mug/ml for cloning efficiency and from 0.86 to 14.6 mug/ml for MTT reduction. The anthrones anthralin and chrysarobin were 4.1 and 3.2 times more toxic, respectively, in the cloning efficiency assay than in the MTT assay. In contrast, the anthraquinones danthron and emodin were 2.8 and 2.1 times more toxic, respectively, in the MTT assay than in the cloning efficiency assay. Among the four mammalian cell lines tested using the MTT assay, the human leukaemia cell line (K562) was the most sensitive to the test chemicals. In contast, anthraquinone toxicity was reduced in rat hepatoma (H4IIE) cultures. In general, structures with carbonyl groups in positions 9 and 10 on the anthracene skeleton (anthraquinones) were less toxic than structures with carbonyl groups in position 9 only (anthrones). Toxicity was also influenced by the position of hydroxy substituents on the tricyclic skeleton. The results suggested that in vitro cytotoxicity assays are useful in elucidating the relationships between structure and biological activity for anthraquinones and related compounds.

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Thirteen bulk pharmaceutical preparations of spironolactone were examined by Fourier transform (FT)-Raman spectroscopy and by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) for residual solvents (including the hydrolysis product, thioacetic acid), the presence of enolic tautomeric forms, and evidence for different polymorphic forms. One sample (L) only was found to contain solvent residue (benzene). No evidence for the possible existence of enolic tautomers in the solid state was found. From these specimens, four different representative polymorphic samples (A, B, C, and D) were selected on the basis of their DRIFTS patterns in the 3600-3200-cm-1 region. Samples K and L were considered to represent mixtures of two or more of the above representative types. Similar differentiation of the samples was made on the basis of their Raman spectra over the frequency range 1800-400 cm-1. The various fundamental stretching frequencies for the C = O and C = C bonds have been assigned, and these assignments, in turn, were used to account for all the bands in the 3600-3200-cm-1 region as overtone and combination frequencies of the fundamentals. The Raman lines at 637 and 655 cm-1 were assigned to the two C-S stretching modes of the thioacetyl moiety.

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Fourier transform Raman and infrared spectra of pure cis(Z)- and trans(E)-2,5-dimethoxy-4,beta-dimethyl-beta-nitrostyrene (precursors of the psychotomimetic street drug STP or DOM) were recorded in the solid state. The spectra show characteristic features of the ethylene moiety and of the aryl and nitro substituents which permit ready differentiation and identification of these isomers. A very strong Raman line at 1670 cm-1 from the cis isomer for the C=C stretching mode, in comparison with a strong Raman line at 1641 cm-1 for the trans isomer, affords primary differentiation of these substances. A second characteristic, of both the Raman and infrared (IR) spectra, is that the frequency of the strong symmetric nitro (NO2) stretching band is about 40 cm-1 higher in the cis (1346 cm-1) than the trans isomer (1301 cm-1). All major IR and Raman bands are reported and given vibrational assignments.

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A method is described for unequivocal identification of dextran sulfate, based on combined chemical desulfation and dextranase enzymolysis of dextran sulfate moieties to isomaltose, a specific indicator of dextran-type precursors. The method was developed using high-resolution (300 MHz) 1H NMR spectroscopy for assurance of the molecular transformations, identification, and estimation of the hydrolysis products. Overall conversion of approximately 80% of highly sulfated and moderately sulfated dextran sulfates was realized. Both 2-D 1H and 13C NMR spectra of a dextran sulfate (MW 500,000) clarified the extent of sulfation (75%) at C-4 and confirmed that sulfation at positions C-2 and C-3 was virtually complete. Estimation of the hydrolysis products (isomaltose, major; alpha-D-glucose, minor) is not restricted to 1H NMR now that the desulfation-enzymolysis methodology has been established; rather, it can be performed using HPLC or GLC (with derivatization).

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Dextran sulfate samples from different sources were examined by 1H and 13C NMR spectroscopy to differentiate the samples on the basis of extent and sites of sulfation. The anomeric (H-1) signal proved to be a good indicator ranging from no sulfation (as in dextran) to virtually complete sulfation at positions 2 and 3, whereas the relative intensity of the H-4 signal afforded a measure, conversely, of the degree of sulfation at position 4. Three different dextran sulfate tablet formulations were found by NMR to contain similar dextran sulfate material that was characterized by a high degree of sulfation at positions 2 and 3. Position 4 of dextran appears to be less readily amenable to substitution. Quasi-elastic light scattering (QELS) analysis of aqueous dispersions of the bulk dextran sulfate samples and formulated tablets permitted additional particle size and homogeneity differentiation. None of the dextran sulfate materials showed either anti-factor Xa activity or marked anticoagulant activity.

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High-field (300 MHz) 1H NMR spectral analysis and particle size distribution analysis employing the quasielastic light scattering (QELS) technique were performed on samples of the 1st International Standard for low molecular weight (LMW) heparin derivatives recently selected by the World Health Organization (WHO). We propose that the results of these analyses, which showed that the material is highly homogeneous in particle size and retains spectral features characteristic of its porcine mucosal origin, form an appropriate basis for physicochemical comparison between the "Standard" and other LMW heparin preparations.

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Several low molecular weight (LMW) heparin sodium derivatives from different sources, as well as some related regular heparin sodium preparations, were examined for chemical composition by high field (300 MHz) 1H NMR spectroscopy, for particle size range by quasi-elastic light scattering (QELS) methods, and for anti-coagulation potency and anti-factor Xa activity by the standard U.S. Pharmacopeial assays described for regular heparin. The NMR spectra provided insight into possible modes of depolymerization used to generate the LMW heparins, as well as into the presence of dermatan sulfate or other chemical contaminants. The QELS analysis permitted the heparin preparations to be characterized and compared by virtue of their distinctive particle size distributions.

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Conditions are described for the preparative LC separation of a bulk nonoxynol-9 material into 16 components. 1H-NMR analyses of these fractions provided evidence for all but the first of the components to be oligomers of nonylphenoxypolyethoxyethanol (nonoxynol) with n-values for (OCH2CH2)n ranging consecutively from 3 to 17, corresponding to the LC fractions 2-16. Mass spectral analysis of the separated LC fractions confirmed the oligomeric sizes deduced from 1H-NMR spectral data, and provided EI fragmentation information for these oligomeric substances.

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A wide range of commercial heparin preparations were examined by the technique of quasi-elastic light scattering (QELS) for size distribution and evidence for aggregation in relation to determined dermatan sulfate (DS) content. No correlation could be found between DS content and state of aggregation. The possible interaction of DS with heparin was further studied by QELS in a control experiment in which known quantities of DS were added to a heparin sodium preparation known to be low in DS. The effect of increasing DS content was to slightly decrease the measured most probable size of the samples and also to decrease the size spread. The biological activity (as measured by the official test) of the heparin samples, including those treated with additional DS, was found to fall within the accepted limits, independent of the aggregation state of the samples. Overall, there is no direct, observable effect that links DS to the observed aggregation of commercial heparin samples, although DS itself is known to self-associate.

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High-field (300 MHz) 1H NMR spectral analyses are reported for various sodium or calcium heparin products available on the Canadian market. Dermatan sulfate (chondroitin sulfate B) was detected as a contaminant in virtually all of these products. Its content varied among the suppliers from less than 1 to 15%, and also over nearly the same range within the groups of heparin preparations of particular suppliers. No correlation was found between in vitro biological activities (potency and anti-factor Xa by the USP tests) and the levels of dermatan sulfate found. Other components, or unlisted constituents, detected in some preparations were paramagnetic metal ions, polyols, and lidocaine.

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The size distribution of heparin aggregates in commercial heparin preparations was examined with the technique of quasi-elastic light scattering. The size distributions were initially examined to determine if any relationship existed between the physical state of the heparin preparation, its age, and its biological activity. It was found that commercial heparin samples change their aggregation state in storage. The amount of aggregation appears to be related to the amount of time in storage and to the storage history. Storage of the samples under conditions of refrigeration and handling represents the storage history that most noticeably increases the aggregation state of the heparin preparations. These aggregates, once formed, appear to be stable. The biological activity of the heparin samples (as measured by the official test) was found to still fall within the accepted limits, independent of the aggregation state of the samples. It is not known what effect, if any, a change in the physical state of the commercial preparation should have on its biological activity.

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3-O-Propanoylmorphine was obtained using the conditions reported earlier for the specific synthesis of 6-O-propanoylmorphine. The latter isomer was synthesized using two different methods; the two compounds were authenticated using IR, MS, carbon-13 and proton NMR.

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The Delvotest P Multi plate test was evaluated by screening 100 milk samples for total antibiotic residues (penicillin G, streptomycin and neomycin). The samples were taken in conjunction with an antibiotic depletion study in milk derived from six cows treated with a multiple antibiotic, intramammary infusion product. Within the limits of sensitivity of the Delvotest, only penicillin G persisted in milk samples taken beyond 60 h, whereas in some samples, the other antibiotics appeared to be depleted as early as 48 h. More sensitive tests, however, detected neomycin ( Staphylococcus epidermidis , ATCC 12228) in 50% of samples taken at 60 h and streptomycin ( Bacillus subtilis , ATCC 6633) at 14.5 d after discontinuation of infusion.