@article {46137, title = {Neural anti-inflammatory natural product periconianone A: total synthesis and biological evaluation}, journal = {European Journal of Organic Chemistry}, year = {2019}, month = {APR }, pages = {2376-2381}, type = {Article}, abstract = {

Total synthesis of periconianone A, an eremophilane-type sesquiterpenoid with impressive neural anti-inflammatory potential, has been accomplished. Diels-Alder/aldol strategy to construct tetrahydro-naphthalene-2,6-dione scaffold, allylic oxidation of dienone using DBU/O-2 and postulated biomimetic aldol reaction to construct 6/6/6 tricyclic system are the highlights of the present synthesis. Furthermore, the synthesized (+/-)-periconianone A and two close analogs were tested for their neural anti-inflammatory activity using various assays. In the course of our study we found a structurally simplified analog is superior to (+/-)-periconianone A.

}, keywords = {Aldol, Allylic oxidation, Biological evaluation, Cytotoxicity, Diels-Alder, Periconianone A}, issn = {1434-193X}, doi = {10.1002/ejoc.201900048}, author = {Kalmode, Hanuman P. and Patil, Suhag S. and Handore, Kishor L. and Athawale, Paresh R. and Dandela, Rambabu and Verma, Abhishek Kumar and Basu, Anirban and Reddy, D. Srinivasa} } @article {46868, title = {Naftopidil molecular salts with improved dissolution and permeation}, journal = {Crystal Growth \& Design}, volume = {20}, year = {2020}, month = {MAY }, pages = {3064-3076}, type = {Article}, abstract = {

Naftopidil (NFPD) is a alpha 1 adrenoceptor antagonist drug. Low solubility and low permeability are the major drawbacks of this drug. The synthesis of multicomponent crystalline forms of this amine functional group drug with carboxylic acid coformers, both achiral and chiral acids, provides a solution to improve its solubility as well as permeability. Nine molecular salts were crystallized by liquid-assisted grinding followed by isothermal crystallization. Single-crystal X-ray diffraction analysis of the molecular salts showed that the structures are stabilized by strong N-H center dot center dot center dot O and O-H center dot center dot center dot O and weak C-H center dot center dot center dot O hydrogen bonds in the solid state. The bulk phase purity of new solid forms was confirmed by powder X-ray diffraction (PXRD), and the crystalline products were further characterized by IR spectroscopy and thermal analytical techniques (differential scanning calorimetry). The molecular salts exhibit superior dissolution rates compared to pure NFPD. However, during dissolution, NFPD showed decrease in concentration after 60 min for all salts due to precipitation. The supersaturation occurred due to salt disproportionation, which generates insoluble NFPD, as confirmed by PXRD of the residue. The salts reach high saturation concentration before 60 min, which is indicative of immediate release formulation to achieve fast onset of therapeutic activity. Moreover, the salts exhibit high saturation in phosphate buffer saline media and improved permeability compared to the pure drug. Finally, the D,L-malic acid racemate of NFPD shows enhanced dissolution and permeability compared to all other salts and pure NFPD.

}, issn = {1528-7483}, doi = {10.1021/acs.cgd.9b01689}, author = {Mannava, M. K. Chaitanya and Dandela, Rambabu and Tothadi, Srinu and Solomon, K. Anand and Nangia, Ashwini K.} } @article {48175, title = {Novel crystal forms of Entresto: a supramolecular complex of trisodium sacubitril/valsartan hemi-pentahydrate}, journal = {Crystengcomm}, volume = {24}, year = {2022}, month = {OCT}, pages = {7387-7393}, type = {Article}, abstract = {

Entresto is a salt-cocrystal supramolecular complex with the chemical name trisodium sacubitril/valsartan hemi-pentahydrate for treating chronic heart failure and was approved by the US FDA in 2015. This multidrug complex was synthesized in our laboratory to investigate its polymorphic behavior. Different crystallization conditions, including various solvent systems, yielded different novel solid forms of Entresto (Form-I to Form-VI), including the reported form. All the novel solids are solvent-dependent and were reproducibly crystallized on a 10 g scale quantity. The 1H NMR spectra confirmed the 1 : 1 stoichiometry of the two drugs, namely, sacubitril and valsartan, in all the solid forms of the crystalline products. Powder X-ray diffraction and DSC analysis of the crystalline solids established that they are distinct crystalline forms. Stability studies under ambient conditions carried out over a one-year period showed higher stability for Form-I and Form-III compared to the other forms, including the innovator crystal form (labelled as Form-II). The novel crystal forms (notably Form-I and Form-III) exhibit higher stability and less hygroscopicity than the reported Form-II.

}, doi = {10.1039/d2ce01009g}, author = {Shaikh, Tabrez R. and George, Christy P. and Bhukya, Priyanka and Shelke, Nikita and Pawar, Komal and Garai, Abhijit and Dandela, Rambabu and Gonnade, Rajesh G. and Nangia, Ashwini K.} } @article {49383, title = {New binary adducts of panobinostat with different carboxylic acid based NSAIDs: structural analysis and physicochemical properties investigation}, journal = {ChemistrySelect}, volume = {9}, year = {2024}, month = {NOV}, pages = {e202403539}, type = {Article}, abstract = {

Adoption of multitarget, cost-effective fixed-dose medication combinations can help lower the pill load without increasing the risk of adverse events. In this study, three new 1:1 drug-drug binary solid forms of panobinostat (PNB) and nonsteroidal anti-inflammatory drugs (NSAIDs) were effectively synthesized by liquid-assisted grinding and slow evaporation crystallization techniques. The obtained solid forms were extensively characterized by various analytical techniques. The structural investigation revealed that all molecular adducts formed salt with a comparable R42\${\textbackslashmathrm{R}}_4\<\^\>2\$(10) graph set pattern created by heteromeric interactions formed between PNB and corresponding salt formers. To determine the dissolving behavior of the newly developed adducts, solubility tests were performed at various pH levels (pH 1.2 and pH 7), and the results indicated that the solubility of all forms is increased at pH 7.0, particularly PNB.NIF has a solubility of 0.195 mg/mL, which is seven times higher than the parent drug. Furthermore, PXRD was used to assess the stability of the synthesized adduct at varied temperature and humidity levels and it was found that all the adducts are stable. Based on the findings, we hope that the newly found PNB drug-drug binary adducts have possible potential to broaden the use of drug combinations without changing the chemical structures.

}, keywords = {Drug-drug salts, Heteromeric interactions, Hydrogen bond, Non-steroidal anti-inflammatory drugs, Panobinostat}, issn = {2365-6549}, doi = {10.1002/slct.202403539}, author = {Kenguva, Gowtham and Rout, Smruti Rekha and Kar, Ananya and Giri, Lopamudra and Shaikh, Tabrez R. and Jadab, Madhusmita and Pal, Satyanarayan and Dandela, Rambabu} } @article {48932, title = {Novel molecular adducts of an anti-cancer drug vandetanib with enhanced solubility}, journal = {Crystengcomm}, volume = {26}, year = {2024}, month = {JAN }, pages = {248-260}, type = {Journal Article}, abstract = {

The solubility, permeability, and dissolution rate of an active pharmaceutical ingredient (API) are critical factors in determining its pharmacokinetic performance in oral dosage forms. Modifying these properties can potentially enhance the drug{\textquoteright}s pharmacokinetics. Vandetanib (VDTB), classified as a class II anti-cancer drug in the biopharmaceutical classification system (BCS), suffers from low solubility (0.008 mg mL-1) and an extended pharmacokinetic half-life (19 days), necessitating the administration of high doses, which leads to undesirable side effects. To address this issue, we have employed a crystal engineering approach to enhance the solubility of VDTB. We employed the liquid-assisted grinding (LAG) method followed by the slow evaporation technique to prepare novel solid forms of VDTB by incorporating various aliphatic dicarboxylic acids, including succinic acid (SUA), adipic acid (ADA), pimelic acid (PIA), azelaic acid (AZA), and sebacic acid (SBA). These newly obtained solid forms were characterized by SC-XRD, PXRD, TGA, and DSC experiments. The crystal structure analyses revealed a proton transfer between the carboxylic acid group of aliphatic acids and the N-methyl piperidine moiety of VDTB, confirming salt/adduct formation. Additionally, all of the molecular salts were stabilized by charge-assisted N+-HMIDLINE HORIZONTAL ELLIPSISO- hydrogen bonds, while the parent VDTB crystal structure is stabilised by N-HMIDLINE HORIZONTAL ELLIPSISN interactions. Moreover, the solubility and dissolution rate of these new solid forms were assessed in a pH 7.4 phosphate buffer medium, with the results indicating that all of the solid forms, except for VDTB:SBA, exhibited higher solubility compared to pure VDTB. These findings offer promising prospects for the development of an improved VDTB formulation with enhanced pharmacokinetic properties. Successful attempt to improve the solubility and dissolution rate of Vandetanib - an anti-cancer drug, by crystal engineering approach.

}, keywords = {Amorfization, hydrate, Parameters, Salt, Thyroid-Cancer}, doi = {10.1039/d3ce01130e}, author = {Bandaru, Ravi Kumar and Giri, Lopamudra and Krishna, Gamidi Rama and Dandela, Rambabu} }