Synthetic crude

FIGURE 1.58 Scavenging of excess catalyst from crude synthetic reaction product. (Reproduced with permission from Biotage AB.)... 

This polypeptide was purified by gradient elution RP-HPLC [Waters 600/486 HPLC system TSK-ODS-120 T column (300 x 21.5mm i.d., Tosoh Corp. Yamaguchi, Japan) 10 pm octadecylsilica eluent A 0.1% TFA/H,0 and B 0.09% TFA in 60% MeCN/H20, linear gradient of 0-100% B over 90 min UV detection (254 nm) flow rate 6.0mL-min-1]. The crude synthetic and purified 110-mer polypeptide, which was obtained from the recovered fractions, was analyzed by analytical RP-HPLC [column as above (150 x 4.6 mm i.d. 5 pm octadecylsilica eluent linear gradient 0-100% B over 60min UV detection (214nm) flow rate lmL-min-1]. b Adapted from Keah and Hearn)14 with permission. 

Figure 17 Elution Profiles for the Analytical RP-HPLC Analysis for the Purified (Insert Panel) and the Preparative RPC of the Crude Synthetic 22-mer Polypeptide Derived from the N-Terminal Secretory Leader Sequence of the Sperm Tail Protein, tpx-1, a Member of the Cystine-Rich Secretory Protein Superfamily 161 ab...

A crude synthetic alcohol is obtained at 15 - 30 per cent alcohol and contains acetaldehyde, oils, butanols, ether and some dissolved C4 - C5 hydrocarbons along with ethylene. It is distilled to remove low and high-boiling impurities and to concentrate to 190 proof. Details of the distillation are often proprietary. A good "spirits" grade of synthetic alcohol is at... 

Fujinary E, Manes JD, Bizanek R, Peptide content determination of crude synthetic peptides by reversed-phase liquid chromatography and nitrogen-specific detection with a chemiluminescent nitrogen detector, J. Chromatogr A, 743 85-89, 1996. 

Retain this chromatogram for future reference as it provides the profile of the original crude synthetic product and can be used to compare syntheses. 

Load the crude synthetic product obtained from the cleavage step directly on to a preparative column through the solvent inlet of the A pump. 

FIGURE 2 Purification of crude synthetic PI4A mellitin by displacement. Column Hy-Tach micropellicular Cl8 silica, I05 X 4.6 mm mobile phase I0% (v/v) acetonitrile in water, 0.1% TFA flow rate 0.2 mL/min temperature 23°C displacer 25 mW benzyl dimethylhexadecyl ammonium chloride feed I0 mg PI4A mellitin (from Kalghatgi et o/.,10 with permission from Elsevier Science). 

Figure 5 Purification of crude synthetic motilin on column of LRP-1 ODS silica. Taken from Coy et al. (21).

Figure 7 Chromatography of crude synthetic secretin eluted on a column (2.5 X 45 cm) of ODS silica LRP-1 (Whatman) (1 3-24 (cm) with a linear gradient of 15 and 35% 1-propanol in 0.1 M ammonium acetate (pH 4) at a flow rate of 5 mL/min and pressure about 60 psi. Taken from Coy et al. (21).

Figure 12 Carboxymethylcellulose chromatography of crude synthetic hACTH. Taken from Yamashiro et al. (101). 20 WILEY ENCYCLOPEDIA OF CHEMICAL BIOLOGY 2008, John Wiley Sons, Inc.

Hydrotreating of heavier feedstocks including petroleum crude, synthetic crudes, and coal liquids. 

The purification of crude synthetic tocopherol acetate by SFE (scC02 as solvent) in a continuous process resulted in high quality material [24] (Fig. 13.1). The process was carried out at 323, 333 and 343 K on 13.6-m columns with a diameter of 35 mm in a pressure range from 16 to 28 MPa. In two separation steps the material was purified to a minimum content of 97 wt-%. 

Figure 8.1. Analysis of trace nickel in Boscan crude, synthetic unknown.

Figure 9-3. RP-HPLC analysis of the crude synthetic analog Tyr3homo-Phe in the reduced lower trace) and disulfide oxidized state upper trace). The chromatographic separations were conducted on a Vydac CIS analytical column (4.6 x 250mm, 5 pm) eluted with a linear acetonitrile-0,05% TFA (.) gradient, at a flow rate of 0.8mL/min.

The crude synthetic pheromone 6 was tested under field conditions. The field traps were made from plastic pipe 6 cm in diameter and wire mesh they were oriented horizontally and permitted wind to pass through. They had funnels formed from wire mesh on the downwind end, which allowed the attracted beetles to enter but which prevented escape. The traps were baited inside either with the pheromone (formulated at 500 /ig per rubber septum), fermenting whole-wheat bread dough (a very effective attractant for C. lugubris 20 g per trap), or a combination of these baits. A piece of screen... 

A brochure published by the International Atomic Energy Agency lists the commercially available preparations, their specific activities and the manufacturers addresses [312]. The commercially available preparations are often very impure and can be used for chemical and biochemical studies only after careful purification. The classical methods for processing crude synthetic products are generally imsatisfactory when applied to small amounts of radioactive compounds. TLC is particularly convenient for purifying radioactive compounds. A detailed account of such preparative applications of the method is given in a special section of this chapter. 

Figure 3.293 Separation of a crude synthetic -20 sequencing primer (17-mer) from its failure sequences. Separator column DNAPac PAIOO column dimensions 250mmx4mm i.d. ...

Figure 3.301 Separation of a crude synthetic RNA 12-mer. Separator column DNAPac PA100 eluent nonlinear gradient from 25 mmol/L Tris-CI + 19 mmol/L NaCI04 (pH 8)...

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