Toward the development of chemoprevention agents (III): Synthesis and anti-inflammatory activities of a new class of 5-glycylamino-2-substituted-phenyl-1,3-dioxacycloalkanes
摘要:
A new series of 5-glycylamino-2-substituted-phenyl-1,3-dioxacycloalkanes were designed and synthesized. The anti-inflammatory activities of these compounds were tested using the xylene-induced mouse ear edema model. Sixteen of these new compounds exhibited comparable or better anti-inflammatory activities than aspirin suggesting that they can be further developed as potential anti-inflammatory drug leads. In addition, treatment with these anti-inflammatory agents did not prolong tail bleeding time in mice. The structure/activity relationships were also analyzed among these compounds. Considering their good efficacy and safety profiles, some 5-glycylamino-2-substituted-phenyl-1,3-dioxacycloalkanes are worthy to be explored further in assessing the possible link between anti-inflammation and cancer prevention. (C) 2007 Elsevier Ltd. All rights reserved.
Conformational Analysis of 5-Substituted 1,3-Dioxanes. 7. Effect of Lithium Bromide Addition,1
摘要:
The position of equilibria, established by means of BF3, between diastereomeric cis- and trans-5-substituted-2-phenyl-1,3-dioxanes, in solvents THF and CHCl3, and in the presence of 0, 1, and 10 equiv of LiBr has been determined. The observed Delta G degrees values show that the addition of salt to the reaction medium influences the position of equilibrium. Lithium bromide effects on the conformational behavior are discussed in terms of lithium ion complexation events that lead to increased stability of the axial isomers when the substituent at C(5) is CO2H, CO2CH3, CONHCH3, and CH2OH. By contrast, disruption of the intramolecular hydrogen bond present in the axial 5-acetamido derivative (cis-9 substituent equal to NHCOCH3) modifies the preference for the axial conformation in salt-free 9 to a net dominance of the equatorial isomer in the presence of LiBr. Interpretation of the experimental observations was based on models that are apparently supported by semiempirical AM1 calculations. The results derived from the present study contribute to our understanding of the processes involved in molecular recognition and may model salt effects in physiological events.
Ammonium Chloride‐Promoted Rapid Synthesis of Monosubstituted Ureas under Microwave Irradiation
作者:Chunling Blue Lan、Karine Auclair
DOI:10.1002/ejoc.202101059
日期:2021.10.7
Ammonium chloride promotes the selective formation of monosubstituted ureas undermicrowaveirradiation. Most nucleophiles, acid-labile functionalities, and protecting groups are well tolerated in this reaction. By avoiding transition metals and mineral acids, this methodology offers a more sustainable alternative for the synthesis of monosubstituted ureas and their analogs.
Toward the development of chemoprevention agents. Part II: Chemo-enzymatic synthesis and anti-inflammatory activities of a new class of 5-amino-2-substitutedphenyl-1,3-dioxacycloalkanes
A new series of optically pure 5-amino-2-substitutedphenyl-1,3-dioxacyclozilkanes were designed and synthesized via a chemo-enzymatic combined method to develop new chemoprevention agents. Twenty-four of newly synthesized compounds significantly inhibited xylene-induced rat ear edema and exhibited comparable or better anti-inflammatory activities than the reference drug aspirin. Treatment of these anti-inflammatory agents did not prolong the tail bleeding time in rat. In addition, 5-amino-2-substitutedphenyl- I 3-dioxacycloalkanes exhibited good membrane permeability based on in vitro Caco-2 cell monolayer permeability assay. Furthermore, some preliminary structure-activity relationships were further analyzed among these compounds. Taken together, 5-amino-2-substitutedphenyl-1,3-dioxacycloalkanes may represent a new class of anti-inflammatory drugs with safer pharmacological profile. (c) 2007 Elsevier Ltd. All rights reserved.
Toward fullerene-based X-ray contrast agents: design and synthesis of non-ionic, highly-iodinated derivatives of C60
作者:Tim Wharton、Lon J Wilson
DOI:10.1016/s0040-4039(01)02119-0
日期:2002.1
An X-ray contrast agent precursor based on C-60 has been designed, synthesized, and characterized. The compound is the monoadduct of a malonodiamide containing six iodine atoms and eight acetal-protected alcohols with multiple hindered rotations at ambient temperature. (C) 2002 Elsevier Science Ltd. All rights reserved.
Highly-Iodinated Fullerene as a Contrast Agent For X-ray Imaging
作者:Tim Wharton、Lon J. Wilson
DOI:10.1016/s0968-0896(02)00252-3
日期:2002.11
The first fullerene-based X-ray contrast agent (CA) has been designed, synthesized, and characterized. The new CA is an externally functionalized derivative Of C-60 that is conceptually based on contemporary X-ray CA, all of which use iodine as the X-ray attenuating vehicle and are based on the 2,4,6-triiodinated-benzene-ring substructure. Using a modified Bingel-type reaction, a single addend containing 6 iodine atoms and 8 protected hydroxyl groups was appended to C-60 followed by the addition of 4 more addends each containing 4 protected hydroxyl groups. Final deprotection afforded the highly water-soluble (>460 mg/mL), non-ionic, highly-iodinated (24% I) fullerene for application as an X-ray contrast agent. (C) 2002 Elsevier Science Ltd. All rights reserved.
Synthesis and CB1 receptor activities of dimethylheptyl derivatives of 2-arachidonoyl glycerol (2-AG) and 2-arachidonyl glyceryl ether (2-AGE)
作者:Teija Parkkari、Outi M.H. Salo、Kristiina M. Huttunen、Juha R. Savinainen、Jarmo T. Laitinen、Antti Poso、Tapio Nevalainen、Tomi Järvinen
DOI:10.1016/j.bmc.2005.12.007
日期:2006.4
Results from a factor analysis and activity studies of commercially available endocannabinoid-type compounds set the starting point for the current study where dimethylheptyl (DMH) analogues of two endocannabinoids, 2-arachidonoyl glycerol (2-AG) and 2-arachidonyl glyceryl ether (2-AGE), were synthesized and their ability to activate the CB1 receptors was determined by the [S-35]GTP gamma S binding assay using rat cerebellar membranes. The main goal of the study was to examine how the DMH end tail affects the activity properties of 2-AG (1) and its stable ether (2) and Urea analogues (5). The importance of the chain length was also explored by synthesizing 2-AG and 2-AGE derivatives (3 and 4) possessing the chain length C-21 instead of C-22. Replacement of the pentyl end chain with the DMH resulted in distinct potency decrease as compared to the reference compounds. The modification did not have Such a strong impact on the efficacy values. In fact, the efficacy of the derivatives of 2-AGE (2 and 4) was comparable or even improved. Introducing a more stable and hydrophilic urea bond led to a dramatic decrease in biological activity. (c) 2005 Elsevier Ltd. All rights reserved.