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Introducing a sulfamide moiety to our coumarin derivatives afforded enhanced Raf/MEK inhibitory activity concomitantly with an acceptable PK profile. Novel sulfamide 17 showed potent HCT116 cell growth inhibition (IC50 = 8 nM) and good PK profile (bioavailability of 51% in mouse), resulting in high in vivo antitumor efficacy in the HCT116 xenograft (ED50 = 4.8 mg/kg). We confirmed the sulfamide moiety showed no negative impact on tests run on the compound to evaluate DMPK (PK profiles in three animal species, CYP inhibition and CYP induction) and the safety profile (hERG and AMES tests). Sulfamide 17 had favorable properties that warranted further preclinical assessment  相似文献   
73.
Bivalent enzyme inhibitors, in which a surface binding module is linked to an active site binding module through a spacer, are a robust approach for site-selectively delivering a minimally-sized agent to a protein surface to regulate its functions, such as protein–protein interactions (PPIs). Previous research revealed that these agents effectively disrupt the interaction between farnesyltransferase (FTase) and the C-terminal region of K-Ras4B protein. However, the whole cell activity of these peptide-based agents is limited due to their low membrane permeability. In this study, we tested a peptidomimetic modification of these bivalent agents using a previously developed inhibitor, FTI-249, and evaluated their cell permeability and biological activity in cells. Confocal cell imaging using fluorescently-labeled agents showed that the peptidomimetic 3-BODIPY penetrated cells, while the peptide-based 1-BODIPY did not. Cell-based evaluation demonstrated that peptidomimetic 3 at a concentration of 100 μM inhibited HDJ-2 processing in cells, indicating that this peptidomimetic modification improves cell permeability, thus leading to enhanced whole cell activity of the bivalent compounds.  相似文献   
74.
In an extension of our study on gamma hydroxy carboxylic acid analogs, we explored a series of nonsecosteroidal vitamin D receptor (VDR) agonists in which 1,3-diol of 1,25(OH)2D3 had been replaced by aryl acetic acid. These analogs showed very potent activity in vitro compared with 1,25(OH)2D3. An X-ray analysis of 8d showed that the inserted phenyl ring well mimicked the folded methylene linker of the gamma hydroxy carboxylic acid moiety but the carboxylic acid of 8d interacted with VDR in a different manner from gamma hydroxy carboxylic acids. Through our in vivo screening in an osteoporosis rat model using immature rats, we identified a potent active vitamin D3 analog, compound 7e. In mature rats of the same model, compound 7e also showed good PK profiling and excellent ability to prevent bone mineral density loss without severe hypercalcemia. Our nonsecosteroidal VDR agonist 7e (CH5036249) could be a possible new drug candidate for treating osteoporosis in human.  相似文献   
75.
We have carried out the optimization of substituents at the C-3 or the C-5 position on the pyrrolidine ring of VLA-4 antagonist 3 with 2-(phenylamino)-7-fluorobenzoxazolyl moiety for the purpose of improving in vivo efficacy while maintaining good aqueous solubility. As a result, we successfully increased in vitro activity in the presence of 3% human serum albumin and achieved an exquisite lipophilic and hydrophilic balance of compounds suitable for oral administrative regimen. The modification resulted in the identification of zwitterionic compound 7n with (5S)-[methoxy(methyl)amino]methylpyrrolidine, which significantly alleviated bronchial hyper-responsiveness to acetylcholine chloride at 12.5 mg/kg, p.o. in a murine asthma model and showed favorable aqueous solubility (JP1, 89 μg/mL; JP2, 462 μg/mL). Furthermore, this compound showed good oral bioavailability (F = 54%) in monkeys.  相似文献   
76.
In connection with disclosure of a new class of insecticides, the modified phenylacetates, six new optically active α-isopropy-4-substituted phenylacetic acids whose substituents are respectively 4-methyl,4-methoxy, 4-fluoro, 4-chloro, 4-bromo and 3,4-methylenedioxy group were prepared by optical resolution and their absolute configurations were determined by comparative ORD with α-isopropylphenylacetic acid derivatives whose absolute configuration is known as (S)-(²). Esters of the (S)-(²)-acids with 5-benzyl-3-furylmethanol were nearly twice toxic to Musca domestica than those of the racemic esters. Optical purities of the resolved acids were determined by GLC and NMR (with Eu-FOD) as (?)-methyl esters.  相似文献   
77.
An attempt has been made to isolate the bacteria capable of accumulating amino acids during the growth at low temperature from various natural sources. A psychrophilic strain P 145 forming glutamic acid at 5°C was obtained and identified as a Brevibacterium sp. The bacterium grew in the range of 0° to 37°C and exhibited the optimum growth at 15°C. The bacterium was defined as a facultative psychrophile.

The strain strictly required methionine only at above 28°C; below this temperature it grew normally without the amino acid. When methionine was added thiamine and biotin stimulated the growth of this strain at 28°C.

With the Brevibacterium sp. P 145 isolated from soil, the effect of incubation temperature on the extracellular amino acid accumulation has been examined from cultural and enzymological points of view. The strain was found to accumulate l-glutamic acid up to 5.88 mg/ml and l-alanine 0.38 mg/ml at 5°C, whereas it formed 0.21 mg/ml of l-glutamic acid and 2.54 mg/ml of l-alanine at 28°C.

The accumulation of l-alanine in the medium at 28°C seemed to be related to the thiamine requirement of the strain. In the case of thiamine deficiency, l-alanine was the main product in the culture at 28°C. When the incubation temperature was abruptly shifted from 28° to 5°C or from 5° to 28°C, the amino acid accumulation was also changed to that of the final temperature. l-Alanine dehydrogenase existed even in the cells grown at 5°C but was not active at this low temperature. These results were in accord with the informations obtained from cultural experiments.  相似文献   
78.
Alzheimer’s disease (AD) is the most common cause of senile dementia. Many inflammatory factors such as amyloid-β and pro-inflammatory cytokines are known to contribute to the inflammatory response in the AD brain. Sphingolipids are widely known to have roles in the pathogenesis of inflammatory diseases, where the precise roles for sphingolipids in inflammation-associated pathogenesis of AD are not well understood. Here we performed a network analysis to clarify the importance of sphingolipids and to model relationships among inflammatory factors and sphingolipids in AD. In this study, we have updated sphingolipid signaling and metabolic cascades in a map of AD signaling networks that we named “AlzPathway,” a comprehensive knowledge repository of signaling pathways in AD. Our network analysis of the updated AlzPathway indicates that the pathways related to ceramide are one of the primary pathways and that ceramide is one of the important players in the pathogenesis of AD. The results of our analysis suggest the following two prospects about inflammation in AD: (1) ceramide could play important roles in both inflammatory and anti-inflammatory pathways of AD, and (2) several factors such as Sphingomyelinase and Siglec-11 may be associated with ceramide related inflammation and anti-inflammation pathways in AD. In this study, network analysis of comprehensive knowledge repository reveals a dual role for ceramide in AD. This result provides a clue to clarify sphingolipids related inflammatory and anti-inflammatory pathways in AD.  相似文献   
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