Targeting Mycobacterium tuberculosis CoaBC through Chemical Inhibition of 4'-Phosphopantothenoyl-l-cysteine Synthetase (CoaB) Activity.

Coenzyme A (CoA) is a ubiquitous cofactor present in all living cells and estimated to be required for up to 9% of intracellular enzymatic reactions. Mycobacterium tuberculosis (Mtb) relies on its own ability to biosynthesize CoA to meet the needs of the myriad enzymatic reactions that depend on this cofactor for activity. As such, the pathway to CoA biosynthesis is recognized as a potential source of novel tuberculosis drug targets. In prior work, we genetically validated CoaBC as a bactericidal drug target in Mtb in vitro and in vivo. Here, we describe the identification of compound 1f, a small molecule inhibitor of the 4'-phosphopantothenoyl-l-cysteine synthetase (PPCS; CoaB) domain of the bifunctional Mtb CoaBC, and show that this compound displays on-target activity in Mtb. Compound 1f was found to inhibit CoaBC uncompetitively with respect to 4'-phosphopantothenate, the substrate for the CoaB-catalyzed reaction. Furthermore, metabolomic profiling of wild-type Mtb H37Rv following exposure to compound 1f produced a signature consistent with perturbations in pantothenate and CoA biosynthesis. As the first report of a direct small molecule inhibitor of Mtb CoaBC displaying target-selective whole-cell activity, this study confirms the druggability of CoaBC and chemically validates this target

Optimization of TAM16, a Benzofuran That Inhibits the Thioesterase Activity of Pks13; Evaluation toward a Preclinical Candidate for a Novel Antituberculosis Clinical Target

[Image: see text] With increasing drug resistance in tuberculosis (TB) patient populations, there is an urgent need for new drugs. Ideally, new agents should work through novel targets so that they are unencumbered by preexisting clinical resistance to current treatments. Benzofuran 1 was identified as a potential lead for TB inhibiting a novel target, the thioesterase domain of Pks13. Although, having promising activity against Mycobacterium tuberculosis, its main liability was inhibition of the hERG cardiac ion channel. This article describes the optimization of the series toward a preclinical candidate. Despite improvements in the hERG liability in vitro, when new compounds were assessed in ex vivo cardiotoxicity models, they still induced cardiac irregularities. Further series development was stopped because of concerns around an insufficient safety window. However, the demonstration of in vivo activity for multiple series members further validates Pks13 as an attractive novel target for antitubercular drugs and supports development of alternative chemotypes

2-Mercapto-Quinazolinones as Inhibitors of Type II NADH Dehydrogenase and Mycobacterium tuberculosis:Structure-Activity Relationships, Mechanism of Action and Absorption, Distribution, Metabolism, and Excretion Characterization

<i>Mycobacterium tuberculosis</i> (<i>MTb</i>) possesses two nonproton pumping type II NADH dehydrogenase (NDH-2) enzymes which are predicted to be jointly essential for respiratory metabolism. Furthermore, the structure of a closely related bacterial NDH-2 has been reported recently, allowing for the structure-based design of small-molecule inhibitors. Herein, we disclose <i>MTb</i> whole-cell structure–activity relationships (SARs) for a series of 2-mercapto-quinazolinones which target the <i>ndh</i> encoded NDH-2 with nanomolar potencies. The compounds were inactivated by glutathione-dependent adduct formation as well as quinazolinone oxidation in microsomes. Pharmacokinetic studies demonstrated modest bioavailability and compound exposures. Resistance to the compounds in <i>MTb</i> was conferred by promoter mutations in the alternative nonessential NDH-2 encoded by <i>ndhA</i> in <i>MTb</i>. Bioenergetic analyses revealed a decrease in oxygen consumption rates in response to inhibitor in cells in which membrane potential was uncoupled from ATP production, while inverted membrane vesicles showed mercapto-quinazolinone-dependent inhibition of ATP production when NADH was the electron donor to the respiratory chain. Enzyme kinetic studies further demonstrated noncompetitive inhibition, suggesting binding of this scaffold to an allosteric site. In summary, while the initial <i>MTb</i> SAR showed limited improvement in potency, these results, combined with structural information on the bacterial protein, will aid in the future discovery of new and improved NDH-2 inhibitors

CD4陽性T細胞に発現するA20(tnfaip3) はTh2型アレルギー性気道炎症を抑制する

研究科: 千葉大学大学院医学薬学府（先端医学薬学専攻）学位記番号: 千大院医薬博甲第医1412号博士（医学）千葉大学 = Chiba Universit

Discovery and optimisation studies of antimalarial phenotypic hits

There is an urgent need for the development of new antimalarial compounds. As a result of a phenotypic screen, several compounds with potent activity against the parasite Plasmodium falciparum were identified. Characterization of these compounds is discussed, along with approaches to optimise the physicochemical properties. The in vitro antimalarial activity of these compounds against P. falciparum K1 had EC50 values in the range of 0.09-29 μM, and generally good selectivity (typically &gt;100-fold) compared to a mammalian cell line (L6). One example showed no significant activity against a rodent model of malaria, and more work is needed to optimise these compounds

Synthesis and antimycobacterial activities of novel 6-nitroquinolone-3-carboxylic acids

Various 1-(substituted)-1,4-dihydro-6-nitro-4-oxo-7-(sub-secondary amino)-quinoline-3-carboxylic acids were synthesized from 2,4-dichlorobenzoic acid by six step synthesis. The compounds were evaluated for antimycobacterial in vitro and in vivo against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant Mycobacterium tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) and also tested for the ability to inhibit the supercoiling activity of DNA gyrase from M. smegmatis. Among the 48 synthesized compounds, 7-(4-((benzo[d][1,3]dioxol-5-yl)methyl)piperazin-1-yl)-1-cyclopropyl-1,4-dihydro-6-nitro-4-oxoquinoline-3-carboxylic acid (8c) was found to be the most active compound in vitro with MIC of 0.08 and 0.16 &#956;M against MTB and MDR-TB, respectively. In the in vivo animal model 8c decreased the bacterial load in lung and spleen tissues with 2.78 and 4.15-log 10 protections, respectively, at the dose of 50 mg/kg body weight

Synthesis, antimycobacterial activities and phototoxic evaluation of 5H-thiazolo[3,2-a]quinoline-4-carboxylic acid derivatives

Thirty four novel 7-fluoro/nitro-1,2-dihydro-5-oxo-8-(sub)-5H-thiazolo[3,2-a]quinoline-4 carboxylic acids were synthesized from 2,4-dichlorobenzoic acid and 2,4-dichloro-5 fluoroacetophenone by multi step reaction, evaluated for in vitro and in vivo antimycobacterial activities against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant Mycobacterium tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) and also tested for the ability to inhibit the supercoiling activity of DNA gyrase from M. smegmatis. Among the synthesized compounds, 8-[6-[[(1,1-dimethylethoxy) carbonyl]amino]-3-azabicyclo[3.1.0]hex-3 yl]-1,2-dihydro-7-nitro-5-oxo-5H-thiazolo[3,2-a]quinoline-4-carboxylic acid (10q) was found to be the most active compound in vitro with MIC of 0.08 mu M and &lt; 0.08 mu M against MTB and MDR-TB respectively. Compound 10q was found to be 4.5 and &gt; 570 times more potent than isoniazid against MTB and MDR-TB respectively. In the in vivo animal model 10q decreased the bacterial load in lung and spleen tissues with 2.51 and 3.71-log10 protections respectively at the dose of 50 mg/kg body weight

Antimycobacterial activities of novel fluoroquinolones

Fifty-one novel 1-(cyclopropyl/2,4-difluorophenyl/t-butyl)-1,4-dihydro-6-fluoro-7-(sub secondary amino)-4-oxoquinoline-3-carboxylic acids were synthesized and evaluated for their antimycobacterial in vitro and in vivo against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant Mycobacterium tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) and also tested for the ability to inhibit the supercoiling activity of DNA gyrase from M. smegmatis. Among the synthesized compounds, 7-(3-(diethylcarbamoyl)piperidin-1-yl)-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (7l) was found to be the most active compound in vitro with MIC of 0.09 &#956;M against MTB and MDR-TB respectively. In the in vivo animal model 7l decreased the mycobacterial load in lung and spleen tissues with 2.53- and 4.88-log10 protections respectively at a dose of 50 mg/kg body weight

Är dagens studenter morgondagens lönsamma bankkunder? -­‐ En fallstudie om studenter som målgrupp inom banksektorn

The fact that many banks today target students with concessional deals is no news. Students are a coveted group at the financial institutions, above all because they will most likely have a secure and well paid occupancy after they have finished their studies. This study will show the importance of banks attracting the students as customers and that the students will continue being customers even after having finalised their studies. It will also show that the banks market themselves towards the students as if students were a homogenous group as well as proving the benefits of calculating a student’s Customer Lifetime Value (CLV). The study is based on research articles within the subject, one interview with the CEO at one of the banks in Sweden and two surveys that were sent out to 10 000 people that are either part of a current student deal at a bank or has been. The result shows that the bank will increase its long-­‐term profitability if it has more students in the customer base. Given that the students remain as customers of the bank after their studies are finished. The results also show the significance of dividing the group "students" based on chosen variables depending on the banks objective and CLV. From this it is concluded that it is less expensive reaching out to the academic meritorious customers in an early stage then to obtain these customers hindsight.Att många banker riktar sig mot studenter med förmånliga erbjudanden är ingen nyhet. Studenter  är  en  eftertraktad  målgrupp  hos  de  finansiella  institutionerna,  framför  allt eftersom chansen är stor att studenter efter studierna kommer att få välbetalda jobb. Den  här  studien  kommer  att  visa  vikten  av  att  banker  attraherar  studenter  som bankkunder och att studenter fortsätter att vara bankkunder efter avslutade studier. Den kommer även visa att banker marknadsför sig mot alla studenter som en homogen målgrupp, samt fördelarna med att räkna ut en students Customer Lifetime Value (CLV). Underlaget till studien är forskningsartiklar och rapporter inom ämnet, en intervju med en VD för en svensk bank och två enkäter som skickats ut till 10 000 personer som antingen är med i ett studenterbjudande hos en bank eller har varit det. Resultaten visar att  banker  skulle  öka  sin  långsiktiga  lönsamhet  om  de  hade  fler  studenter  som bankkunder, förutsatt att de stannar kvar som kunder efter avslutade studier. Resultatet visar även  betydelsen av  att  dela upp  studenterna i  mindre delsegment efter valda variabler beroende på bankens målsättning och CLV. Utifrån detta dras slutsatsen att det är mindre kostsamt att nå ut till de akademiskt meriterade kunderna i ett tidigt skede än att erhålla dessa kunder i efterhand