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Tuberculosis (TB) is a disease caused by Mycobacterium and usually attack the lung. Synthesis of new dipeptide derivatives attached to antitubercular active heterocyclic rings like pyrazine and 1,3,4-oxadiazole called ethyl 2-(2-(5-((pyrazin-2-ylamino) methyl)-1,3,4-oxadiazol-2-ylthio) acetamido) acetamido)-3-(4-hydroxyphenyl) propanoate (EPOGTP) and iodinated EPOGTP are reported. The compounds have been characterized by mass, FT-IR and 1H NMR spectroscopy. Their in vitro investigation against Mycobacterium tuberculosis cell line indicated good IC50value of 210 μg/ml for EPOGTP and 86 μg/ml for iodo-EPOGTP. For study the biodisriution, the direct radioiodination of EPOGTP with iodine-131 using mild oxidizing agent, N-Bromosuccinimide (NBS), was performed and optimized for obtaining the maximum radiochemical purity (97.3 ± 0.47%). Then, the in vivo biodistribution in healthy mice showed good accumulation of radioiodinated EPOGTP in lung of about 41.83 ± 0.23% (the percentage of injected dose per gram of organ) at 15 min post-injection. As a conclusion, the synthetized dipeptide and its iodinated derivative could be further evaluated as a potential antitubercular agents.

One-pot expedient and direct carbamolyation of heterocyclics is described. The transformation is realized via direct dehydrogenative aminocarbonylation of heterocyclic compounds under transition-metal-free conditions. This method is regioselective and the protocol is proved to be scalable on a gram scale. Further, the therapeutically useful antitubercular agent pyrazinecarboxamide is successfully synthesized by employing this protocol

Thiazolidinediones are sulfur containing pentacyclic compounds that are widely found throughout nature in various forms. Thiazolidinedione nucleus is present in numerous biological compounds, e.g., anti-malarial, antimicrobial, anti-mycobacterium, anticonvulsant, antiviral, anticancer, anti-inflammatory, antioxidant, anti-HIV (human immunodeficiency virus) and antitubercular agent. However, owing to the swift development of new molecules containing this nucleus, many research reports have been generated in a brief span of time. Therefore seems to be a requirement to collect recent information in order to understand the current status of the thiazolidinedione nucleus in medicinal chemistry research, focusing in particular on the numerous attempts to synthesize and investigate new structural prototypes with more effective antidiabetic, antimicrobial, antioxidant, anti-inflammatory, anticancer and antitubercular activity.

An efficient P2O5 mediated protocol for the synthesis of pyrido[2,3-d:6,5-d]dipyrimidines has been developed through one-pot three-component condensation of aromatic aldehydes, barbituric acid/thiobarbituric acid, and 1,3-dimethyl-6-amino-uracil in ethanol. All the synthesized products were screened for their in vitro antitubercular activity, and results reveal that most of the compounds exhibited moderate to good activity against Mycobacterium tuberculosis H37RV strain.

In this work, four series of tertiary amine-containing derivatives of 3,5-dinitrophenyl tetrazole and oxadiazole antitubercular agents were prepared, and their in vitro antimycobacterial effects were evaluated. We found that the studied compounds showed lipophilicity-dependent antimycobacterial activity. The N-benzylpiperazine derivatives, which had the highest lipophilicity among all of the series, showed the highest in vitro antimycobacterial activities against Mycobacterium tuberculosis CNCTC My 331/88 (H37Rv), comparable to those of the first-line drugs isoniazid and rifampicin. The presence of two tertiary amines in these N-benzylpiperazine derivatives enabled us to prepare water-soluble dihydrochloride salts, overcoming the serious drawback of previously described 3,5-dinitrophenyl tetrazole and oxadiazole lead compounds. The water-soluble 3,5-dinitrophenyl tetrazole and oxadiazole antitubercular agents described in this work are good candidates for further in vitro and in vivo pharmacokinetic and pharmacodynamic studies.

Thirty-three meso-dihydroguaiaretic acid (meso-DGA) derivatives bearing esters, ethers, and amino-ethers were synthesized. All derivatives were tested against twelve drug-resistant clinical isolates of Gram-positive and Gram-negative bacteria, including sensitive (H37Rv) and multidrug-resistant Mycobacterium tuberculosis strains. Among the tested compounds, four esters (7, 11, 13, and 17), one ether (23), and three amino-ethers (30, 31, and 33) exhibited moderate activity against methicillin-resistant Staphylococcus aureus, whereas 30 and 31 showed better results than levofloxacin against vancomycin-resistant Enterococcus faecium. Additionally, nineteen meso-DGA derivatives displayed moderate to potent activity against M. tuberculosis H37Rv with minimum inhibitory concentration (MIC) values ranging from 3.125 to 50µg/mL. Seven meso-DGA derivatives bearing amino-ethers (26-31 and 33) exhibited the lowest MICs against M. tuberculosis H37Rv and G122 strains, with 31 being as potent as ethambutol (MICs of 3.125 and 6.25µg/mL). The presence of positively charged group precursors possessing steric and hydrophobic features (e.g. N-ethylpiperidine moieties in meso-31) resulted essential to significantly increase the antimycobacterial properties of parent meso-DGA as supported by the R-group pharmacophoric and field-based QSAR analyses. To investigate the safety profile of the antimycobacterial compounds, cytotoxicity on Vero cells was determined. The amino-ether 31 exhibited a selectivity index value of 23, which indicate it was more toxic to M. tuberculosis than to mammalian cells. Therefore, 31 can be considered as a promising antitubercular agent for further studies.

Introduction: Introducing new and effective antitubercular agents is important in tuberculosis control programs. In this study, the in vitro antitubercular activity of two novel 1,4-dihydropyridine derivatives (F-27, Cl-33) were screened against a total of 113 different strains of Mycobacterium tuberculosis (77 susceptible and 36 resistant clinical isolates). Methodology: The in vitro activities of these compounds were evaluated based on the modified broth macro-dilution assay. Results: Compound F-27 showed more than 90% growth inhibition at the range of 2 to 8 μg/mL (minimum inhibitory concentration [MIC]90: 4.13 ± 0.45 µg/mL; p < 0.01), and complete growth inhibition was observed at the range of 8 to 32 μg/mL (minimum bactericidal concentration [MBC]: 11.2 ± 1.65 µg/mL; p < 0.01) against susceptible strains. However, 92% of the resistant strains showed some degree of susceptibility against this compound (MIC90 range: 16 to 64 µg/mL; mean: 40.4 ± 8 µg/mL; p < 0.01). It was found that although there is a linear relationship between the inhibitory activity of F-27 and isoniazid against resistant strains at low concentrations (r = 0.484, p < 0.001), there was no relationship between resistance to isoniazid and F-27 at higher concentrations (r = 0.019, p > 0.1). This may emphasize no cross-resistance between F-27 and isoniazid. Conclusions: Considering the sufficient sample size of the study and based on the excellent antimycobacterial activity of F-27, it could be concluded that F-27 is a potent candidate as a lead compound, and may be considered for development of a new antitubercular agent.

We report herein one-pot synthesis and the antibacterial and antitubercular activities of 2,5-disubstituted-1,3,4-oxadiazole compounds obtained by hybridization of a well-known antitubercular agent isoniazid (INH) with four broad-spectrum antibiotics belonging to fluoroquinolone (FQ) class. The work is aimed at designing and developing potential antimicrobial agents having synergistic action due to the coupling of INH and FQ through the biologically active 1,3,4-oxadiazole nucleus. The synthesized compounds are expected to have low toxicity as compared to INH due to the absence of free hydrazide group in the chemical structure of the prepared derivatives. The antibacterial activities of the 1,3,4 oxadiazole derivatives were also tested against several Gram-positive and Gram-negative pathogenic bacterial strains. The antitubercular activity was evaluated against M. tuberculosis H37Rv strain, and the results were compared with that of the positive control INH. The title compounds showed excellent antimicrobial and promising antitubercular activity in comparison to the parent fluoroquinolones and INH, respectively.

Following up the SAR study of triazolothiadiazoles for their antitubercular activities targeting Mt SD in our previous study, on the principle of scaffold hopping, the C3 and C6 positions of triazolothiadiazine were examined systematically to define a preliminary structure-activity relationship (SAR) with respect to biological activity. This study herein highlights the potential of two highly potent advanced leads 6c-3, 6g-3 and several other compounds with comparable potencies as promising new candidates for the treatment of TB (6c-3, MIC-H37Rv=0.25μg/mL; MIC-MDRTB=2.0μg/mL; MIC-RDRTB=0.25μg/mL; Mt SD-IC50=86.39μg/mL; and 6g-3, MIC-H37Rv=1.0μg/mL; MIC-MDRTB=4.0μg/mL; MIC-RDRTB=2.0μg/mL; Mt SD-IC50=73.57μg/mL). Compounds 6c-3 and 6g-3 possessed a para-nitro phenyl at the 6 position showed low Vero and HepG2 cells toxicity, turning out to be two excellent lead candidates for preclinical trials. In addition, in vitro Mt SD inhibitory assay indicates that Mt SD is at least one of the targets for their antitubercular activity. Thus, they may turn out to be promising multidrug-resistance-reversing agents.

Objectives: Biomarkers for tuberculosis (TB) diagnosis and clinical management are needed to defeat TB. In chronic hepatitis, patients not responding to interferon/ribavirin treatment had high levels of an antagonist form of IP-10. Recently, antagonist IP-10 has been shown to be involved also in TB pathogenesis. Here, we investigated IP-10 agonist/antagonist forms as potential inflammatory biomarkers to support TB diagnosis and monitoring. Methods: Total IP-10 and its agonist/antagonist forms were measured by SIMOA digital ELISA in urine obtained from patients with active TB at baseline and after treatment. Healthy donors (HD) and patients with pneumonia were enrolled as controls. Results: Patients with active TB had significantly higher levels of total and agonist IP-10 at baseline compared to HD; conversely, no differences were observed between IP-10 levels in active TB vs pneumonia. Moreover, in active TB a decline of total urine IP-10 was observed at therapy completion; agonist/antagonist forms reflected this decline although their differences were not statistically significant. Conclusions: We showed for the first time that agonist/antagonist IP-10 forms are measurable in urine. IP-10 levels associate with TB and pneumonia disease, suggesting their association with acute inflammation. Further studies are needed to assess their role to monitor TB treatment efficacy. Keywords: Tuberculosis, Biomarker, IP-10 antagonism, Urine, Treatment monitoring

In this study, the N,N,O metal chelator 2-pyridinecarboxaldehydeisonicotinoyl hydrazone (HPCIH, 1) and its derivatives 2-acetylpyridine-(HAPIH 2), 2-pyridineformamide-(HPAmIH, 3) and pyrazineformamide-(HPzAmIH, 4) were employed in the synthesis of four copper(II) complexes, [Cu(HPCIH)Cl2]·0.4H2O (5), [Cu(HAPIH)Cl2]·1.25H2O (6), [Cu(HPAmIH)Cl2]·H2O (7) and [Cu(HPzAmIH)Cl2]·1.25H2O (8). The compounds were assayed for their action toward Mycobacterium tuberculosis H37Rv ATCC 27294 strain and the human tumor cell lines OVCAR-8 (ovarian cancer), SF-295 (glioblastoma multiforme) and HCT-116 (colon adenocarcinoma). All copper(II) complexes were more effective in reducing growth of HCT-116 and SF-295 cells than the respective free hydrazones at 5 µg/mL, whereas only complex 7 was more cytotoxic toward OVCAR-8 lines than its ligand HPAmIH. 6 proved to be cytotoxic at submicromolar doses, whose IC50 values (0.39–0.86 µM) are similar to those ones found for doxorubicin (0.23–0.43 µM). Complexes 5 and 6 displayed high activity against M. tuberculosis (MIC = 0.85 and 1.58 µM, respectively), as compared with isoniazid (MIC = 2.27 µM), which suggests the compounds are attractive candidates as antitubercular drugs.

Isoniazid is a key antitubercular agent which exhibits poor chemical stability in the solid state. Cocrystallization with hydroxyl derivatives of cinnamic acid, which themselves possesses antitubercular and antioxidant activity, may produce solid forms with improved pharmaceutical properties. The complementary nature of the functional groups of isoniazid and the chosen coformers resulted in a high success rate for cocrystal formation. The three previously unknown cocrystal forms, plus a new polymorph were characterized by solid-state NMR, DSC, PXRD and single crystal XRD. Three previously known cocrystals were also synthesized and characterized. NMR chemical shifts were observed to distinguish between a key synthon involving the carboxylic acid of cinnamic acid.

In a search of new antitubercular agents, herein we have reported a series of new thirty-two indanol-1,2,3-triazole derivatives. The synthesized compounds were screened for their in vitro antitubercular and antimicrobial activities. Among the screened compounds, most of the compounds have displayed good antitubercular activity against Mycobacterium tuberculosis H37Rv. The compound 5g has been identified as potent antitubercular agent with MIC value 1.56 µM. The most active compounds of the series were further studied for their cytotoxicity against HEK 293 cells using MTT assay and found to be nontoxic. In addition, ten compounds were shown good antimicrobial activities against both antibacterial and antifungal pathogens. A molecular docking study against Mycobacterial enoyl-ACP-reductase (InhA) was performed to gain an insight into the molecular mechanism of antitubercular action. The pharmacokinetic parameters of these compounds were studied and displayed acceptable drug-likeness score.

The aim of this study was to synthesize newer potent Schiff bases by condensing 2-amino-5-(2,4-dichlorophenyl)thiophene-3-carbonitrile and 1,3-disubstituted-1H-pyrazole-4-carbaldehydes, and to investigate their biological activity. The compounds were synthesized via Gewald synthesis and characterized by spectral data and elemental analyses. They were screened for their in vitro antibacterial and anti-inflammatory activities. The synthesized compounds were also evaluated for in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv using the microplate Alamar Blue assay. Compounds 8b, 8c, 8f, 8g, 8k, 8n, and 8o showed promising antibacterial activity. The interactions between the substituted pyrazoles and bovine protein showed promising anti-inflammatory activity. The experimental results revealed compound 8a as a promising antitubercular agent. Hemolytic assays confirmed that the compounds are nontoxic, with percentage hemolysis ranging from 3.6 to 20.1, at a concentration of 1 mg/ml. The results suggest that the pyrazole ring and the substitution pattern on the heterocyclic moiety have an effect on the bioactivity.

Development of novel, safe and effective drug candidates combating the emerging drug resistance has remained a major focus in the mainstream of anti-tuberculosis research. Here, we inspired to design and synthesize series of new pyridin-4-yl-1,3,4-oxadiazol-2-yl-thio-ethylidene-hydrazinecarbothioamide derivatives as potential anti-tubercular agents. The anti-tubercular bioactive assay demonstrated that the synthesized compounds exhibit potent anti-tubercular activity (MIC = 3.9–7.81 μg/mL) in comparison with reference drugs Rifampicin and Isoniazid.We employed pharmacophore probing approach for the identification of CYP51 as a possible drug target for the synthesized compounds. To understand the preferable binding mode, the synthesized molecules were docked onto the active site of Sterol 14 α-demethylases (CYP51) target. From the binding free energy of the docking results it was revealed that the compounds were effective CYP51 inhibitors and acts as antitubercular agent.

Objective To analyze the clinical and laboratory features and determine the predictors of acute liver failure (ALF) among inpatients with anti-tuberculosis (TB) drug-induced liver injury (DILI). Method Patients diagnosed with anti-TB DILI from 2010 to 2016 at The First Affiliated Hospital of Zhejiang University were retrospectively included in this study. Demographic and clinical data were collected by reviewing electronic medical records. Results Among 155 inpatients with anti-TB DILI, 55 (35.48%) developed ALF, with an overall mortality of 9.68%. The median time to DILI onset was significantly longer in the ALF compared with the non-ALF group (51 versus 24 days). Eighty-three patients (53.55%) developed DILI (53.55%) within the first month of anti-TB treatment, and 60% of ALF cases occurred within 2 months. Multivariable models for ALF incorporating aspartate aminotransferase, total bilirubin, platelets, white blood cell count, and pre-existing hepatitis yielded a concordance (C-statistic) of 98.93%. Conclusions The results of this study suggest that approximately half of all cases of DILI occur within the first month, while 60% of ALF cases occur within 2 months. Elevated total bilirubin, aspartate aminotransferase, white blood cell count, pre-existing hepatitis, and low platelet count are independent risk factors for the development of anti-TB drug-induced ALF.

The development of versatile antitumor agents with tumor-imaging, targeting and therapeutic activity is promising for clinical cancer therapy. Prostate cancer is still the one of the leading threats to males. Current therapies have restricted clinical efficiency for patients with advanced and metastatic prostate cancer. Recent studies demonstrate that monoamine oxidase A (MAOA) levels elevate with prostate cancer aggression and metastasis. In addition, MAOA inhibitor therapies have been reported as an effective means to reduce the metastasis of prostate cancer and extend mouse survival. Thus, these findings provide evidence that MAOA is promising for the treatment of metastatic and advanced prostate cancer. Herein, three isoniazid (INH)–dye conjugates were synthesized by conjugating MAOA inhibitor INH with mitochondria-targeting NIRF heptamethine dyes to improve the therapeutic efficacy of prostate cancer. These INH–dye conjugates could accumulate in PC-3 cellular mitochondria via organic anion transport peptide (OATP), increase ROS generation, and induce cancer cells apoptosis. In prostate cancer bearing xenografts, INH–dye conjugates showed significantly improved tumor-homing characteristics, resulting in potent antitumor activity via a reduction in MAOA activity. These results suggest that INH–dye conjugates have great potential to be used as versatile antitumor agents with prostate cancer targeting, NIR imaging, and potent antitumor efficacy.

The optimization campaign for a nitrofuran antitubercular hit (N-benzyl-5-nitrofuran-2-carboxamide; JSF-3449) led to the design, synthesis, and biological profiling of a family of analogs. These compounds exhibited potent in vitro antitubercular activity (MIC = 0.019–0.20 μM) against the Mycobacterium tuberculosis H37Rv strain and low in vitro cytotoxicity (CC50 = 40–>120 μM) towards Vero cells. Significant improvements in mouse liver microsomal stability and mouse pharmacokinetic profile were realized by introduction of an α, α-dimethylbenzyl moiety. Among these compounds, JSF-4088 is highlighted due to its in vitro antitubercular potency (MIC = 0.019 μM) and Vero cell cytotoxicity (CC50 > 120 μM). The findings suggest a rationale for the continued evolution of this promising series of antitubercular small molecules.

The development of an effective antitubercular agent is a challenge due to the complex nature of tuberculosis. Herein, we report the synthesis and evaluation of α-aminoacyl amides as antitubercular agents. The systematic medicinal chemistry approach led to identification of optimal substitutions required for the activity. Compound 11l was identified as antitubercular lead with drug like properties. Further, 11l selectively inhibited M. tuberculosis H37Rv with MIC value of 0.78 μM and was found to be non-toxic to CHO K1 cells. The lead compound inhibited multidrug resistant and Pre-Extensively drug resistant strains of Mycobacterium at 2 μg/mL and 8 μg/mL respectively.

In our efforts to develop druggable diphenyl ethers as potential antitubercular agents, a series of novel diphenyl ether derivatives (5a-f, 6a-f) were designed and synthesized. The representative compounds showed promising in vitro activity against drug-susceptible, isoniazid-resistant, and multidrug-resistant strains of Mycobacterium tuberculosis with MIC values of 1.56 μg/ml (6b), 6.25 μg/ml (6a-d), and 3.125 μg/ml (6b-c), respectively. All the synthesized compounds exhibited satisfactory safety profile (CC50 > 300 μg/ml) against Vero and HepG2 cells. Reverse phase HPLC method was used to probe the physicochemical properties of the synthesized compounds. This series of compounds demonstrated comparatively low logP values. pKa values of representative compounds indicated that they were weak acids. Additionally, in vitro human liver microsomal stability assay confirmed that the synthesized compounds possessed acceptable stability under study conditions. The present study thus establishes compound 6b as the most promising antitubercular agent with acceptable drug-likeness.

This article reports the recommendations for managing neonatal tuberculosis (TB) drawn up by a group of Italian scientific societies. The Consensus Conference method was used, and relevant publications in English were identified through a systematic review of MEDLINE and the Cochrane Database of Systematic Reviews from their inception until 31 December 2014. Group experts concluded that if suspicion is aroused, it is necessary to undertake promptly all of the investigations useful for identifying the disease not only in the newborn, but also in the mother and family contacts because a diagnosis of TB in the family nucleus can guide its diagnosis and treatment in the newborn. If the suspicion is confirmed, empirical treatment should be started. Breast-fed newborns being treated with isoniazid should be given pyridoxine supplementation at a dose of 1 mg kg(-1) day(-1). Mothers with active-phase TB can breast-feed once they have become smear negative after having received appropriate treatment.

Differences in clinical characteristics and outcome between elderly (>60years) and younger (18–59years) tuberculosis (TB) patients were retrospectively evaluated. Alcohol abuse, radiological evidence of cavitation, and cough at presentation were more frequent among younger patients. Older patients were more likely to have comorbidities, disseminated TB, longer duration of symptoms and higher TB-related mortality (19 vs 0%). Very old patients (≥80 years) showed increased liver toxicity and hospital acquired infections compared to patients aged 60–79years.

Emergence of multi-drug resistant tuberculosis (MDR-TB) and HIV-TB co-infections potentiate the development of newer antitubercular agents to combat against tuberculosis, a dreadful disease. In the present investigation a series of pyrazoline analogues were designed and synthesized based on the structure of known antitubercular agent thiacetazone, in hope of obtaining new and safe antitubercular agents. The target molecules were synthesized in two steps, starting with the condensation of 4-aminoacetophenone and p -anisidine in methanolic sodium hydroxide solution followed by the cyclization of intermediate chalcones with appropriate semicarbazide/thiosemicarbazide in glacial acetic acid. All the synthesized compounds were characterized by 1 H NMR, IR and mass spectral data and the purity of the compounds was checked by elemental analysis. Their antimycobacterial activity was evaluated by two folds serial dilution method. 3-(4-Aminophenyl)- N -(4-chlorophenyl)-4,5-dihydro-5-(4-methoxyphenyl)pyrazole-1-carboxamide ( 4i ) showed maximum activity against Mycobacterium tuberculosis H37Rv with minimum inhibitory concentration (MIC) of 7.41 μM.

In this study, we synthesized two series of novel 5-nitrofuran-2-carbohydrazides 21a-h and 22a-e in addition to a third series of thiophene-2-carbohydrazides 23a-g to develop potent antimicrobial and/or antitubercular agents. The newly synthesized compounds were evaluated in vitro for their antimicrobial and antimycobacterial activities. Most of the 5-nitrofuran-2-carbohydrazides 21a-h and 22a-e displayed variable activity against Aspergillus fumigates, Staphylococcus aureus, Streptococcus pneumonia, Bacillis subtilis, Salmonella typhimurium, Klebsiella pneumonia, Escherichia coli and Mycobacterium tuberculosis. The sulfonamide derivative 21f exhibited superior potency and broad-spectrum antimicrobial activity with minimum inhibitory concentration (MIC)=0.06-0.98 µg/mL and antimycobacterial activity with MIC=3.9 µg/mL. The 5-nitrofuran-2-carbohydrazides 21a, b, g, h and 22a-c exhibited significant antibacterial activity with MIC values in the range of 0.12-7.81 µg/mL. The significances of the 5-nitrofuran moiety and sulfonamide function were explored via the structure-activity relationship (SAR) study. In addition, docking studies revealed that the p-amino benzoic acid (PABA) and binding pockets of the dihydropteroate synthase (DHPS) were successfully occupied by compound 21f. Furthermore, two quantitative structure-activity relationship (QSAR) models were built to explore the structural requirements which controlled the activity.

Tuberculosis (TB) takes the second place among the reasons for mortality from infectious diseases. For this reason, the problem of tuberculosis treatment requires urgent attention all over the world. Some 2-amino substituted 1,3-benzothiazin-4-ones (2-amino-1,3-BTZs) represent a promising new class of antitubercular agents. Other 1,3-benzothiazin-4-one derivatives, mostly 2-aryl and 2- (pyridin-2-yl) ones, are attractive due to their ability to suppress oxidative stress-induced cardiomyocyte apoptosis. This review covers the synthetic approaches to 2-amino- and 2-aryl(heteryl) substituted 1,3-benzothiazin-4-ones (1,3-BTZs). A brief overview of structure-activity relationships is presented.

A set of fused ring analogues of a new antitubercular agent, Q203, was designed and synthesized. To reduce the lipophilicity of Q203 caused by linearly extended side chains, shorter and heteroatoms containing fused rings were introduced into the side chain region. Antitubercular activity was tested against H37Rv-GFP replicating in liquid broth culture medium (extracellular) and within macrophages (intracellular). Many analogues showed potent extracellular activities as well as intracellular activities without cytotoxicity. Among them, compounds 18–21 displayed significant antitubercular activities with favorable metabolic stabilities. Representative compound 21 exhibited excellent in vivo pharmacokinetic values at high drug exposure levels in the plasma, which makes this compound promising candidate for a new antitubercular drug.

Active tuberculosis (TB) and latent Mycobacterium tuberculosis infection both require lengthy treatments to achieve durable cures. This problem has partly been attributable to the existence of nonreplicating M. tuberculosis “persisters” that are difficult to kill using conventional anti-TB treatments. Compounds that target the respiratory pathway have the potential to kill both replicating and persistent M. tuberculosis and shorten TB treatment, as this pathway is essential in both metabolic states. We developed a novel respiratory pathway-specific whole-cell screen to identify new respiration inhibitors. This screen identified the biphenyl amide GSK1733953A (DG70) as a likely respiration inhibitor. DG70 inhibited both clinical drug-susceptible and drug-resistant M. tuberculosis strains. Whole-genome sequencing of DG70-resistant colonies identified mutations in menG ( rv0558 ), which is responsible for the final step in menaquinone biosynthesis and required for respiration. Overexpression of menG from wild-type and DG70-resistant isolates increased the DG70 MIC by 4× and 8× to 30×, respectively. Radiolabeling and high-resolution mass spectrometry studies confirmed that DG70 inhibited the final step in menaquinone biosynthesis. DG70 also inhibited oxygen utilization and ATP biosynthesis, which was reversed by external menaquinone supplementation. DG70 was bactericidal in actively replicating cultures and in a nutritionally deprived persistence model. DG70 was synergistic with the first-line TB drugs isoniazid, rifampin, and the respiratory inhibitor bedaquiline. The combination of DG70 and isoniazid completely sterilized cultures in the persistence model by day 10. These results suggest that MenG is a good therapeutic target and that compounds targeting MenG along with standard TB therapy have the potential to shorten TB treatment duration. IMPORTANCE This study shows that MenG, which is responsible for the last enzymatic step in menaquinone biosynthesis, may be a good drug target for improving TB treatments. We describe the first small-molecule inhibitor (DG70) of Mycobacterium tuberculosis MenG and show that DG70 has characteristics that are highly desirable for a new antitubercular agent, including bactericidality against both actively growing and nonreplicating mycobacteria and synergy with several first-line drugs that are currently used to treat TB.

The new drugs delamanid and bedaquiline are increasingly being used to treat multidrug-resistant (MDR-) and extensively drug-resistant tuberculosis (XDR-TB). The World Health Organization, based on lack of evidence, recommends their use under specific conditions and not in combination. No systematic review has yet evaluated the efficacy, safety, and tolerability of delamanid and bedaquiline used in combination. A search of peer-reviewed, scientific evidence was carried out, aimed at evaluating the efficacy/effectiveness, safety, and tolerability of delamanid and bedaquiline-containing regimens in individuals with pulmonary/extrapulmonary disease, which were bacteriologically confirmed as M/XDR-TB. We used PubMed to identify any relevant manuscripts in English up to the 23 December 2016, excluding editorials and reviews. Three out of 75 manuscripts retrieved satisfied the inclusion criteria, whilst 72 were excluded for dealing with only one drug (three studies), being recommendations (one study) or identifying need for their use (one study), focusing on drug resistance aspects (six studies) or being generic reviews/other studies (61 papers). The studies retrieved reported two XDR-TB cases observed for six months and achieving consistent sputum smear and culture conversion. Case 2 experienced a short break of bedaquiline, which was re-started after introducing verapamil. After a transient and symptom-free increase of the QT interval from week 5 to 17, it then decreased below the 500 ms threshold.

This study aimed to develop clinically feasible models of limited sampling strategy (LSS) for estimation of the area under the concentration–time curve (AUC 24h) for isoniazid, that could be applied easily in daily clinical practice for dosage adjustment in adult patients with tuberculosis. Isoniazid plasma concentrations ( n =1665) from 185 adult tuberculous patients were used for the development and validation of LSS models to estimate AUC 24h following administration of the standard 5 mg/kg dose of isoniazid. Population pharmacokinetic analysis for appropriate estimation of isoniazid pharmacokinetic parameters was performed in a modelling group ( n =100). The Bayesian estimates of AUC 24h (AUC ref ) obtained for each individual were used as the dependent variable in the regression analysis for the development of various LSS models. The LSS models were validated in a separate cohort ( n =85). Several three and four time point LSS models were built and tested. Model H (AUC 24h =-1.88 + 1.05 × C 1 + 0.78 × C 2 + 9.44 × C 5 ) and Model I (AUC 24h =-0.65 + 1.00 × C 1 + 1.94 × C 2 + 15.45 × C 9 ) had the best performances [adj- R 2 =0.93, median prediction error (MPE)=-0.20, root median squared prediction error (RMSE)=4.65 for Model H; adj- R 2 =0.96, MPE=-0.05 RMSE=3.56 for Model I]. The very high R 2 values (≥0.97) of these regression equations in the validation cohort confirmed their high reliability. These LSS models could be applied in the context of therapeutic drug monitoring programmes aiming to personalize isoniazid dosing regimens for adult patients with tuberculosis.

A series of 1-(substituted-phenyl)-1-[(2-chloroquinolin-3-yl)methyl]thiocarbamide and 1-(substituted-phenyl)-1-[(2-chloroquinolin-3-yl)methyl]methylthiocarbamide derivatives was synthesized as antitubercular agent. The structure of quinolinyl amines and their thiocarbamide derivatives were established on the basis of IR, (1)H and (13)C-NMR and mass spectral data. All the compounds were tested in vitro for antimycobacterial activity against Mycobacterium tuberculosis (ATCC-25177) in Lowenstein-Jensen medium by well diffusion method and MIC by twofold serial dilution method. Results of the antitubercular screening revealed that compounds showed moderate to good antitubercular activity. Compound having two halogens in the phenyl rings viz. 3g, 3h, 4g, and 4h exhibited MIC of 50 μg/mL. The computational parameters relevant to absorption and permeation of target compounds were also calculated and found to be well correlated with antitubercular activity.

To the Editor: The European Respiratory Society (ERS) and the World Health Organization (WHO) Regional Office for Europe implemented a consultation body, the ERS/WHO Tuberculosis (TB) Consilium, in late April 2013 [1–4]. This is a novel, high-priority initiative, as part of the 2012–2013 Presidential plan, to face the growing problem of drug-resistant TB in Europe and globally to support clinicians in managing difficult-to-treat TB cases. Clinicians are increasingly challenged by difficult-to-treat cases of multidrug-resistant (MDR)-TB ( i.e. TB caused by Mycobacterium tuberculosis strains resistant to isoniazid and rifampicin) and extensively drug-resistant (XDR)-TB ( i.e. TB caused by MDR-TB strains that are also resistant to at least one fluoroquinolone and one injectable second-line anti-TB drug) [5–8]. MDR/XDR-TB is seriously hampering TB control and elimination in Europe [9–11], as patients require long and expensive regimens with significant adverse effects, while cure rates remain low [7, 8, 12–14]. Clinicians can upload a case description and queries via the ERS/WHO TB Consilium website (www.tbconsilium.org), the process of which takes up to 20 minutes. The case is then assigned to global experts who provide feedback to the clinician’s questions in a limited timeframe, free of charge. At the time of writing, the TB Consilium has provided expert opinion on 51 cases (and two outbreaks from 11 countries), with an average response time of 36 h. The most frequently posed questions are related to the design and duration of the most appropriate regimens for difficult-to-treat patients [4]. In the absence of a sufficient number of medicines to which a strain is sensitive in vivo , life-saving treatment may rely on the use of new medicines (bedaquiline or delamanid) either under conditional or through compassionate use [15– …

Treatment of latent tuberculosis infection (LTBI) is a key component in TB control strategies worldwide. However, as people with LTBI are neither symptomatic nor contagious, any screening decision should be weighed carefully against the potential benefit of preventing active disease in those who are known to be at higher risk and are willing to accept therapy for LTBI. This means that a targeted approach is desirable to maximize cost effectiveness and to guarantee patient adherence. We focus on LTBI treatment strategies in patient populations at increased risk of developing active TB, including candidates for treatment with tumor necrosis factor-α blockers. In the last 40 years, isoniazid (INH) has represented the keystone of LTBI therapy across the world. Although INH remains the first therapeutic option, alternative treatments that are effective and associated with increased adherence and economic savings are available. Current recommendations, toxicity, compliance, and cost issues are discussed in detail in this review. A balanced relationship between the patient and healthcare provider could increase adherence, while cost-saving treatment strategies with higher effectiveness, fewer side effects, and of shorter duration should be offered as preferred.

The World Health Organization (WHO) recommends that countries implement pharmacovigilance and collect information on active drug safety monitoring (aDSM) and management of adverse events.The aim of this prospective study was to evaluate the frequency and severity of adverse events to anti-tuberculosis (TB) drugs in a cohort of consecutive TB patients treated with new (i.e. bedaquiline, delamanid) and repurposed (i.e. clofazimine, linezolid) drugs, based on the WHO aDSM project. Adverse events were collected prospectively after attribution to a specific drug together with demographic, bacteriological, radiological and clinical information at diagnosis and during therapy. This interim analysis included patients who completed or were still on treatment at time of data collection.Globally, 45 centres from 26 countries/regions reported 658 patients (68.7% male, 4.4% HIV co-infected) treated as follows: 87.7% with bedaquiline, 18.4% with delamanid (6.1% with both), 81.5% with linezolid and 32.4% with clofazimine. Overall, 504 adverse event episodes were reported: 447 (88.7%) were classified as minor (grade 1–2) and 57 (11.3%) as serious (grade 3–5). The majority of the 57 serious adverse events reported by 55 patients (51 out of 57, 89.5%) ultimately resolved. Among patients reporting serious adverse events, some drugs held responsible were discontinued: bedaquiline in 0.35% (two out of 577), delamanid in 0.8% (one out of 121), linezolid in 1.9% (10 out of 536) and clofazimine in 1.4% (three out of 213) of patients. Serious adverse events were reported in 6.9% (nine out of 131) of patients treated with amikacin, 0.4% (one out of 221) with ethionamide/prothionamide, 2.8% (15 out of 536) with linezolid and 1.8% (eight out of 498) with cycloserine/terizidone.The aDSM study provided valuable information, but implementation needs scaling-up to support patient-centred care.

Rational: Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are emerging problems in several countries. These infections require long and expensive treatment regimens. Recently, 2 new drugs, bedaquiline and delamanid, have been approved in several countries for use in adults with severe, difficult-to-treat MDR-TB, and it has been suggested that they could also be administered to children with MDR-TB and limited treatment options. However, no study has been completed on their efficacy. Patient concerns: This report describes a 12-year-old child with XDR-TB who was cured after a 24-month therapy regimen, which included delamanid. Diagnoses: The patient showed progressive clinical deterioration after 5 months of treatment with the majority of anti-TB drugs available on the market. Interventions: After unsuccessfull treatment with several anti-TB drugs for 5 months, he was treated with a regimen including for 24 months. Outcomes: Direct smear microscopy of the gastric aspirates and gastric aspirate cultures for Mycobacterium tuberculosis became negative after only 1 week and remained persistently negative. During the 24-month treatment, all blood test results remained within the normal range, no adverse events were reported, and corrected QT interval was always normal. A clinical and laboratory control was performed 3 months after discontinuation of delamanid, and the other drugs did not reveal any modification of both general conditions as well as laboratory and radiological findings. The patient was considered cured. Lessons: The positive outcome associated with the favorable safety and tolerability profile showed that long-term therapy with delamanid can significantly contribute to treating apparently hopeless XDR-TB cases in children.

Background Active tuberculosis (TB) is commonly considered a contraindication for liver transplantation (LT). However, in patients with TB who develop acute liver failure (ALF) due to toxicity induced by anti-tubercular treatment (ATT), LT could be the only opportunity for treatment. The aim of this study was to evaluate the feasibility of LT in this scenario. Methods We described 2 cases and comprehensively reviewed the literature finding 26 cases of LT performed in patients having a concomitant active TB and liver failure secondary to ATT toxicity. Results TB was classified as pulmonary in 18/26 (69%), nodal in 3/26 (11%) TB cases, while the remaining 5/26 cases included disseminated, pleural, renal, ovarian, and vertebral TB localization (1 case each). ATT following LT consisted mainly of isoniazid or rifampin (RIF)-sparing regimens and included primarily fluoroquinolones and ethambutol. Rejection episodes and liver toxicity were reported in 19% and 8% of patients respectively. Graft rejection was more frequent among patients treated with RIF-containing regimens (P

The developing countries are having an abruptly growing number of drug resistant tuberculosis cases. Multidrug-resistant tuberculosis (MDR-TB) is a type of TB in which the strain of Mycobacterium tuberculosis is resistant to at least Isoniazid and Rifampicin, the two most effective of the four first-line TB drugs (the other two drugs being Ethambutol and Pyrazinamide). The management of such cases is complex and requires a treatment for 24-27 months. The current guidelines available for the management of this type of TB are largely based on the second line TB drugs which are relatively costly, less efficacious and are associated with greater side-effects. The introduction of newer drugs to cater to the high mortality and early sputum culture conversion in the MDR-TB cases is an absolute essential. In the present article, the authors discuss about the introduction of a newer drug named Bedaquiline for the control of MDR-TB.

In migrants coming to Italy from 106 countries, MDR-TB was high from the former Soviet Union and low from Africa http://ow.ly/WZDbo

This document describes the recommendations of a group of scientific societies concerning the first-line therapeutic approach to paediatric tuberculosis (TB). The treatment of pulmonary TB should be based on the existence of parenchymal involvement and the risk of antibiotic resistance. The treatment of extra-pulmonary TB is based on the regimens used for severe pulmonary TB. The administration of corticosteroids is recommended only in cases of miliary TB, tuberculous meningitis and tuberculous pericarditis. Vitamin B6 may be indicated in the case of isoniazid-treated TB in breastfeeding infants, severely malnourished subjects, or patients with other diseases at high risk of vitamin deficiency. Once having started treatment, children with TB should be carefully followed up in order to evaluate compliance, the response to treatment, the need for treatment changes, and the presence of drug-related adverse events. Primary care paediatricians can support reference centres in providing family healthcare education and encouraging treatment compliance.

Fused pyrazolopyranopyrimidines containing both biologically active pyranopyrazole and pyranopyrimidine compounds were synthesized using a one-pot, four-component reaction of ethyl aceto acetate, hydrazine hydrate, benzaldehydes, and thiobarbituric acid without catalyst in ethanol. All target compounds obtained in very good to excellent yields over short reaction times by adapting a simple workup procedure. All the synthesized compounds exhibited good to excellent antituberculosis activities. The results shown that 4-(1H-imidazol-2-yl)-3-methyl-7-thioxo-4,6,7,8-tetrahydropyrazolo[4’,3′:5,6]pyrano[2,3-d] pyrimidin-5(1H)-one (5a) is a good antitubercular agent, as good as the standard streptomycin drug, based on minimum inhibitory concentration (MIC).

No large study has ever evaluated the efficacy, safety and tolerability of meropenem/clavulanate to treat multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB). The aim of this observational study was to evaluate the therapeutic contribution, effectiveness, safety and tolerability profile of meropenem/clavulanate added to a background regimen when treating MDR- and XDR-TB cases.Patients treated with a meropenem/clavulanate-containing regimen (n=96) showed a greater drug resistance profile than those exposed to a meropenem/clavulanate-sparing regimen (n=168): in the former group XDR-TB was more frequent (49% versus 6.0%, pversus 5 (4–6)). Patients were treated with a meropenem/clavulanate-containing regimen for a median (IQR) of 85 (49–156) days.No statistically significant differences were observed in the overall MDR-TB cohort and in the subgroups with and without the XDR-TB patients; in particular, sputum smear and culture conversion rates were similar in XDR-TB patients exposed to meropenem/clavulanate-containing regimens (88.0% versus 100.0%, p=1.00 and 88.0% versus 100.0%, p=1.00, respectively). Only six cases reported adverse events attributable to meropenem/clavulanate (four of them then restarting treatment).The nondifferent outcomes and bacteriological conversion rate observed in cases who were more severe than controls might imply that meropenem/clavulanate could be active in treating MDR- and XDR-TB cases.