Other Biological Activities

niger CGC has been shown to prevent the early development of atherosclerosis in an in-vivo animal study [190], In that study, Syrian golden hamsters were fed with a hyperlipidic diet and the test animal group received a daily dose of CGC. The results showed that CGC did not affect plasma cholesterol but lowered triglycerides, reduced the aortic fatty streak accumulation and improved the antioxidant status. 

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Potcntiomctric Biosensors Potentiometric electrodes for the analysis of molecules of biochemical importance can be constructed in a fashion similar to that used for gas-sensing electrodes. The most common class of potentiometric biosensors are the so-called enzyme electrodes, in which an enzyme is trapped or immobilized at the surface of an ion-selective electrode. Reaction of the analyte with the enzyme produces a product whose concentration is monitored by the ion-selective electrode. Potentiometric biosensors have also been designed around other biologically active species, including antibodies, bacterial particles, tissue, and hormone receptors. 

D. H. Schlesinger, ed.. Neurohypophyseal Peptide Hormones and Other Biologically Active Peptides, Developments in Endocrinology, Vol. 13, Elsevier Science, New York, 1981. 

Numerous other biological activities have been claimed for many synthetic quinoxalines and these are well documented in the review by Cheeseman and Cookson (79HC(35)l). 

Mammals can add additional double bonds to unsaturated fatty acids in their diets. Their ability to make arachidonic acid from linoleic acid is one example (Figure 25.15). This fatty acid is the precursor for prostaglandins and other biologically active derivatives such as leukotrienes. Synthesis involves formation of a linoleoyl ester of CoA from dietary linoleic acid, followed by introduction of a double bond at the 6-position. The triply unsaturated product is then elongated (by malonyl-CoA with a decarboxylation step) to yield a 20-carbon fatty acid with double bonds at the 8-, 11-, and 14-positions. A second desaturation reaction at the 5-position followed by an acyl-CoA synthetase reaction (Chapter 24) liberates the product, a 20-carbon fatty acid with double bonds at the 5-, 8-, IT, and ITpositions. 

Many other biologically active pyrroles have been prepared by this reaction. 3-Cyano-3,4-disubsdnited pyrroles are prepared by thereacdon ofisocyanoacetonitnie v/ithfi-nitro acetates. 

A new aspect of the PC-pathway is the efficacy of recombinant-APC in reducing mortality in patients with septic shock. Whether this is related to the inhibition of thrombin generation or due to other biological activities of APC is currently under investigation. 

The benzodiazepine nucleus is extremely important, as it is the base of several drugs and other biologically active compounds with different properties. A facile synthesis of 2-methyl-l,4-benzodiazepin-5-ones has been described by Santagada and co-workers [162]. Isatoic anhydride 254 was reacted with M-substituted allylamines under microwave irradiation to give compound 255... 

Bergmann D, Hinze J (1987) Electronegativity and Charge Distribution. 66 145-190 Berners-Price SJ, Sadler PJ (1988) Phosphines and Metal Phosphine Complexes Relationship of Chemistry to Anticancer and Other Biological Activity. 70 27-102 Bertini I, see Banci L (1990) 72 113-136... 

The herbicide activity ascribed to the 1,2,4-oxadiazole derivative 67 (60) has prompted the search for other biologically active derivatives. This example was prepared from the corresponding 5-chloromethyl-1,2,4-oxadiazole 63 via conversion to the HHT 65 through the aminomethyl analog 64. Reaction of the HHT 65 with diethyl phosphite under neat conditions produced the desired diethyl ester intermediate 66, which was hydrolyzed to 67. 

A Brief Review of the QSAR Technique. Most of the 2D QSAR methods employ graph theoretic indices to characterize molecular structures, which have been extensively studied by Radic, Kier, and Hall [see 23]. Although these structural indices represent different aspects of the molecular structures, their physicochemical meaning is unclear. The successful applications of these topological indices combined with MLR analysis have been summarized recently. Similarly, the ADAPT system employs topological indices as well as other structural parameters (e.g., steric and quantum mechanical parameters) coupled with MLR method for QSAR analysis [24]. It has been extensively applied to QSAR/QSPR studies in analytical chemistry, toxicity analysis, and other biological activity prediction. On the other hand, parameters derived from various experiments through chemometric methods have also been used in the study of peptide QSAR, where partial least-squares (PLS) analysis has been employed [25]. 

The a -, /z-, and a-conotoxins are the best characterized of the peptides isolated from Conus venoms so far. However, a large number of other peptides are found in these venoms. These comprise both paralytic toxins to immobilize the prey of the cone snail, and other biologically active peptides which are not themselves directly paralytic. Only the briefest overview of these peptide components will be presented here. 

The Staudinger reaction [92], a [2 + 2]-cycloaddition of a ketene and a nucleophilic imine, usually proceeds by an initial imine attack on the ketene thus forming a zwitterionic enolate which subsequently cyclizes. This reaction is an expedient route to p-lactams, the core of numerous antibiotics (e.g., penicillins) and other biologically active molecules [93]. In contrast, for Lewis-base catalyzed asymmetric reactions, nonnucleophilic imines are required (to suppress a noncatalyzed background reaction), bearing, for example, an N-Ts [94] or -Boc-substituent [95]. 

In each of the assays of potency the amount of the immunoglobulin and the amount of a corresponding standard preparation that are required to neutralize the infectivity or other biological activity of a defined amount of virus or to neutralize a defined amount of a bacterial toxin are determined. The two determined amounts and the assigned unitage of the standard preparation are then used to calculate the potency of the immunoglobulin in International Units (lU). ELISA, enzyme-linked immunosorbent assay. 

The synthesis of other biologically active thiazoles was described by Ohsumi et al. [50] and is shown in Scheme 16. Condensation of phosphonium bromide and 4-methoxy-3-nitrobenzaldehyde gave a 1 1 mixture of (Z)- and (-E)-stilbenes. ( )-stilbene 64 was purified by crystallization and then converted to bromohydrin 65 by NBS-H2O. Oxidation of the bromohydrin by DMSO-TFAA gave the bromoketone intermediate 66, which was condensed with thiocarbamoyl compounds in the presence of Na2C03 in DMF to give the corresponding 2-substituted thiazole derivatives (67a and b). Compound 67a... 

Takada, H. and S. Kotani, Structural Requirements of Lipid-a for Endotoxicity and Other Biological Activities, CRC Critical Reviews in Microbiology. 16, 477, 1989. 

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