Infrared absorption bands, assignment

B, respectively. The infrared absorption bands assignments for sodium valproate and valproic acids are shown in Table 2(A) and (B), respectively. 

For these measurements, a Foxboro/Wilks Model 80 Computing Infrared Analyzer and a Perkin-Elmer Model 281B Infrared Spectrophotometer have been used. Infrared absorption band assignments in the carbonyl region are summarized in Table II (y, 2, 3, 9-17). 

In 1951, Witkop et al. interpreted the infrared spectra of quinol-2-and -4-ones to favor the oxo formulation. Since then, many investigators, especially Mason, have reported that potential a- and y-hydroxy compounds show infrared absorption bands in the vN—H (3500-3360 cm ) and vC—O (1780-1550 cm ) regions of the spectrum and, hence, exist predominantly in the oxo form references to this work appear in Table I. A study of the bands which occur in the NH-stretching region of the infrared spectra of a series of substituted pyrid-2-ones and quinol-2-ones also supported an oxo formulation for these compounds. Detailed band assignments have been published for pyrid-2- and -4-one. Mason has reported that solutions of j8-hydroxy compounds in chloroform or carbon tetrachloride show... 

Infrared absorption bands of S (n>2) complexes are usually of low intensity, while the Raman spectra often show intense and characteristic hnes. However, the assignments are difficult because of their complexity. The absorptions in electronic spectra are often assigned to intrahgand transitions, and it is known that the increasing length of the polysulfido chain leads to an increasing red shift of the absorption band. 

The infrared absorption spectrum of miconazole nitrate was obtained in a KBr pellet using a Perkin-Elmer infrared spectrophotometer. The IR spectrum is shown in Fig. 4, where the principal peaks were observed at 3140, 3070, 2995, 2920, 1566, 1525, 1445, 1385, 1310, 1070, and 710 cm-1. Assignments for the major infrared absorption band are provided in Table 2. Clarke reported principal peaks at 1085, 1319, 827, 1302, 1038, and 812 cm-1 (miconazole nitrate, KBr disc) [2]. 

Table 2. Vibrational assignments for miconazole nitrate infrared absorption bands...

Table 2. Assignments for the main infrared absorption bands of penicillamine...

The infrared (IR) absorption spectrum of primaquine diphosphate was obtained as KBr disc using a Perkin-Elmer infrared spectrometer. The infrared spectrum is shown in Fig. 4 and the principal peaks are at 2946, 1612, 1469, 1430, 1384, 1200, 1050, 956, 815, and 760 cm-1. The assignments of the infrared absorption bands of primaquine diphosphate are shown in Table 2. Clarke reported the following principal peaks at 1611, 1595, 815, 1230, 1572, and 1170 cm-1 (KBr disk) [2],... 

A. Assignments for the infrared absorption bands of sodium valproate ... 

Assignments for the Infrared Absorption Bands of Chlorpromazine Hydrochloride... 

Assignments for the Major Observed Infrared Absorption Bands... 

Assignments for the Characteristic Infrared Absorption Bands of Procaine HCl... 

It is not possible to dissolve the asphaltenes in water by treatment of the halo derivatives with aqueous sodium hydroxide or with aqueous sodium sulfite (II). The hydrolyzed products remained insoluble even in a strongly alkaline solution. The decreased (H + Cl)/C ratios and the increased O/C ratios of the products relative to those of the parent halo-asphaltenes indicate that partial reaction occurs. The infrared spectra of the products showed a broad band centered at 3450 cm 1, a region assigned to the presence of hydroxyl groups in the products, but it was not possible to establish conclusively the presence of sulfonic acid group(s) in the product from the sodium sulfite reaction by assignment of infrared absorption bands to this particular group. 

TABLE 1.4 Assignment for the characteristic infrared absorption bands of atorvastatin calcium... 

The infrared spectrum of a mineral oil mull of vitamin D3 recorded on a Model FTS 15E instrument (Digilab, Cambridge, Mass.) is shown in Figure 2 (18). Table I shows assignments for the significant infrared absorption bands (18). 

Energies and Assignments for the Major Infrared Absorption Bands of Etodolac... 

The copper(I) alkynyls displayed rich photochemistry and particularly strong photoreducing properties. The transient absorption difference spectrum of [Cu3(dppm)3(/X3-) -C=CPh)2]+ and the electron acceptor 4-(methoxycarbonyl)-A-methylpyridinium ion showed an intense characteristic pyridinyl radical absorption band at ca. 400 nm. An additional broad near-infrared absorption band was also observed and it was assigned as an intervalence-transfer transition of the mixed-valence transient species [Cu Cu Cu (dppm)3(/x3- -C=CPh)2] +. The interesting photophysical and photochemical properties of other copper(I) alkynyl complexes such as [Cu(BTA)(hfac)], 2 [Cui6(hfac)8(C=C Bu)8], and [Cn2o(hfac)8(CsCCH2Ph)i2] have also been studied. 

TABLE 6.5 Assignments of the infrared absorption bands of lornoxicam... 

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