endo-11-(Dibenzyl­amino)­tetra­cyclo­[5.4.0.03,10.05,9]undecane-8-one

The structure of the title compound, C25H27NO, is a mono-ketone penta­cyclo­undecane (PCU) mol­ecule bearing a tertiary amine group. One of the methyl­ene groups in the PCU is disordered over two orientations with site-occupancy factors of 0.621 (7) and 0.379 (7)

Benzyl 5-hy­droxy-4-oxapenta­cyclo­[5.4.1.02,6.03,10.08,11]dodecane-3-carboxyl­ate

The title compound, C19H18O4, exhibits a long C—C bond [1.575 (2) Å] in the cage structure. In the crystal, pairs of O—H⋯O hydrogen bonds link the mol­ecules into centrosymmetric dimers. C—H⋯O inter­actions also occur

tert-Butyl N-[(11-exo-benzyl­oxy­carbonyl-8-oxopenta­cyclo­[5.4.0.02,6.03,10.05,9]undecane-11-endo-yloxy)carbon­yl­methyl]carbamate

The structure of the title compound, C26H29NO7, at 173 K has an inter­molecular N—H⋯O hydrogen bond. This is one of the few examples where a mono-ketone penta­cyclo­undecane (PCU) mol­ecule exibits hydrogen bonding in the solid state. The dihedral angles of the amide and ester groups are normal and unaffected by the cage structure. A longer than normal C—C bond [1.571 (4) Å] was found within the cage structure

Crystal structure of the Eg5 - K858 complex and implications for structure-based design of thiadiazole-containing inhibitors

The thiadiazole scaffold is an important core moiety in a variety of clinical drug candidates targeting a range of diseases. For example, the 2,4,5-substituted 1,3,4-thiadiazole scaffold is present in a lead compound and at least two clinical candidates targeting the human motor protein Eg5, against neoplastic diseases. An inhibitor named K858 has in vivo activity in various mouse xenografts whereas the clinical candidates (S)-ARRY-520 and (R)-Litronesib have entered clinical trials with the former one in phase III clinical trials either alone or in combination with a proteasome inhibitor against relapsed/refractory multiple myeloma. Astonishingly, structural data are lacking for all thiadiazole-containing Eg5 inhibitors. Here we report the structure determination of two crystal forms of the ternary Eg5-ADP-K858 complex, locking the motor in the so-called final inhibitor bound state, thus blocking ADP release, a crucial stage for Eg5 activity. K858 acts at the established allosteric inhibitor-binding pocket formed of helix α2, loop L5 and helix α3. The structure of the complex has far reaching consequences for thiadiazole containing Eg5 inhibitors. For example, we could rationalise the structure-activity relationship in the crucial 5-position of the thiadiazole scaffold and the complex will serve in the future as a basis for strucutre-based drug design

In search of selective 11β-HSD type 1 inhibitors without nephrotoxicity: An approach to resolve the metabolic syndrome by virtual based screening

Over expression of 11β-HSD 1 in key metabolic tissues is related to the development of type 2 diabetes, obesity, hypertension and metabolic syndrome. Nephrotoxicity of corosolic acid (selective inhibitor of 11β-HSD 1) is recently reported, which is one of the major drawback. Therefore, it is of great interest to find out the selective 11β-HSD 1 inhibitors without nephrotoxicity. Using crystal structures of 11β-HSD 1 in complex with inhibitors as a source of structural information, a combined structure-based virtual screening approach followed by PASS toxicity prediction, Lipinski’s rule and ADME prediction was implemented to find out the potent and selective 11 β-HSD 1 analog of corosolic acid without nephrotoxicity. Two compounds with NCBI compound identification number CID59752459 (Genins of Asiatic acid) and CID 119034 (Asiatic acid) were found to be selective for the 11β-HSD 1 enzyme without nephrotoxicity which comply with Lipinski’s rule and ADME parameter defined for human use. However, none of the hits inhibited 11β-HSD 2 at 100 μM indicating their selectivity against 11β-HSD 1

Cytochrome P450 Monooxygenase CYP139 Family Involved in the Synthesis of Secondary Metabolites in 824 Mycobacterial Species

Tuberculosis (TB) is one of the top infectious diseases causing numerous human deaths in the world. Despite enormous efforts, the physiology of the causative agent, Mycobacterium tuberculosis, is poorly understood. To contribute to better understanding the physiological capacity of these microbes, we have carried out extensive in silico analyses of the 1111 mycobacterial species genomes focusing on revealing the role of the orphan cytochrome P450 monooxygenase (CYP) CYP139 family. We have found that CYP139 members are present in 894 species belonging to three mycobacterial groups: M. tuberculosis complex (850-species), Mycobacterium avium complex (34-species), and non-tuberculosis mycobacteria (10-species), with all CYP139 members belonging to the subfamily “A”. CYP139 members have unique amino acid patterns at the CXG motif. Amino acid conservation analysis placed this family in the 8th among CYP families belonging to different biological domains and kingdoms. Biosynthetic gene cluster analyses have revealed that 92% of CYP139As might be associated with producing different secondary metabolites. Such enhanced secondary metabolic potentials with the involvement of CYP139A members might have provided mycobacterial species with advantageous traits in diverse niches competing with other microbial or viral agents, and might help these microbes infect hosts by interfering with the hosts’ metabolism and immune system

An Unprecedented Number of Cytochrome P450s Are Involved in Secondary Metabolism in Salinispora Species

Cytochrome P450 monooxygenases (CYPs/P450s) are heme thiolate proteins present in species across the biological kingdoms. By virtue of their broad substrate promiscuity and regio- and stereo-selectivity, these enzymes enhance or attribute diversity to secondary metabolites. Actinomycetes species are well-known producers of secondary metabolites, especially Salinispora species. Despite the importance of P450s, a comprehensive comparative analysis of P450s and their role in secondary metabolism in Salinispora species is not reported. We therefore analyzed P450s in 126 strains from three different species Salinispora arenicola, S. pacifica, and S. tropica. The study revealed the presence of 2643 P450s that can be grouped into 45 families and 103 subfamilies. CYP107 and CYP125 families are conserved, and CYP105 and CYP107 families are bloomed (a P450 family with many members) across Salinispora species. Analysis of P450s that are part of secondary metabolite biosynthetic gene clusters (smBGCs) revealed Salinispora species have an unprecedented number of P450s (1236 P450s-47%) part of smBGCs compared to other bacterial species belonging to the genera Streptomyces (23%) and Mycobacterium (11%), phyla Cyanobacteria (8%) and Firmicutes (18%) and the classes Alphaproteobacteria (2%) and Gammaproteobacteria (18%). A peculiar characteristic of up to six P450s in smBGCs was observed in Salinispora species. Future characterization Salinispora species P450s and their smBGCs have the potential for discovering novel secondary metabolites

Dehydrozingerone Inspired Styryl Hydrazine Thiazole Hybrids as Promising Class of Antimycobacterial Agents

Series of styryl hydrazine thiazole hybrids inspired from dehydrozingerone (DZG) scaffold were designed and synthesized by molecular hybridization approach. <i>In vitro</i> antimycobacterial activity of synthesized compounds was evaluated against <i>Mycobacterium tuberculosis</i> H₃₇Rv strain. Among the series, compound <b>6o</b> exhibited significant activity (MIC = 1.5 μM; IC₅₀ = 0.48 μM) along with bactericidal (MBC = 12 μM) and intracellular antimycobacterial activities (IC₅₀ = <0.098 μM). Furthermore, <b>6o</b> displayed prominent antimycobacterial activity under hypoxic (MIC = 46 μM) and normal oxygen (MIC = 0.28 μM) conditions along with antimycobacterial efficiency against isoniazid (MIC = 3.2 μM for INH-R1; 1.5 μM for INH-R2) and rifampicin (MIC = 2.2 μM for RIF-R1; 6.3 μM for RIF-R2) resistant strains of Mtb. Presence of electron donating groups on the phenyl ring of thiazole moiety had positive correlation for biological activity, suggesting the importance of molecular hybridization approach for the development of newer DZG clubbed hydrazine thiazole hybrids as potential antimycobacterial agents

In search of selective 11β-HSD type 1 inhibitors without nephrotoxicity: An approach to resolve the metabolic syndrome by virtual based screening

AbstractOver expression of 11β-HSD 1 in key metabolic tissues is related to the development of type 2 diabetes, obesity, hypertension and metabolic syndrome. Nephrotoxicity of corosolic acid (selective inhibitor of 11β-HSD 1) is recently reported, which is one of the major drawback. Therefore, it is of great interest to find out the selective 11β-HSD 1 inhibitors without nephrotoxicity. Using crystal structures of 11β-HSD 1 in complex with inhibitors as a source of structural information, a combined structure-based virtual screening approach followed by PASS toxicity prediction, Lipinski’s rule and ADME prediction was implemented to find out the potent and selective 11 β-HSD 1 analog of corosolic acid without nephrotoxicity. Two compounds with NCBI compound identification number CID59752459 (Genins of Asiatic acid) and CID 119034 (Asiatic acid) were found to be selective for the 11β-HSD 1 enzyme without nephrotoxicity which comply with Lipinski’s rule and ADME parameter defined for human use. However, none of the hits inhibited 11β-HSD 2 at 100μM indicating their selectivity against 11β-HSD 1