Dr. Kartik D. Ladva
@vsc.edu.in
Principal
Shree Manibhai Virani and Smt. Navalben Virani Science College, Rajkot
EDUCATION
M.Sc., Ph.D.
RESEARCH INTERESTS
Organic Chemistry, Heterocyclic Chemistry, Medicinal Chemistry
Scopus Publications
Scopus Publications
Vishvraj V. Devmurari, Poojaben P. Patel, Rajeshreeba A. Jadeja, Cameykumari P. Bhadaniya, Priti P. Aghara, Anilkumar S. Patel, Satishkumar D. Tala, Mahesh M. Savant, Kartik D. Ladva, and Pankajkumar B. Nariya
Pensoft Publishers
Aim: To extract and identify the non-polar entities from the leaves of Carica papaya, a plant used for medicinal purpose as folk medicine. Materials and methods: Petroleum ether extract of the Carica papaya leaves was used for this study. Saponification process and methylation process was performed to separate fatty acids and unsaponifiable matters. Phytochemical constituents were separated using chemical process and separated fractions were analyzed by thin layer chromatography (TLC) and gas chromatography coupled with mass spectroscopy (GC-MS). Results: The chemical composition of the steroids, triterpenoids and fatty acid methyl esters (FAMEs) in leaves of Carica papaya, which were analyzed by gas chromatography coupled with mass spectroscopy (GC-MS). A total of 15 fatty acid components were identified in saponifiable matter, from unsaponifiable portion 2 steroids (campesterol, β- or γ-sitosterol), 1 triterpene (squalene), and 1 diterpene (phytol) were identified. Conclusions: The results indicate that the extract is rich in non-polar compounds. In this study, GC-MS method is at the central focus for identification of these phytoconstituents. The current method can be used for direct analysis of non-polar entities of plant material.
SHOBHANA A. GADARA and KARTIK D. LADVA
Asian Journal of Chemistry
A new series of triazolo[4,3-a]pyimidine derivatives via solid phase multicomponent reaction between 3-oxo-N-(4-(3-oxomorpholino)- phenyl)butanamide, aromatic aldehyde and aminoazole is reported. All the synthesized compounds have been characterized by elemental analysis and spectral analyses. Moreover, the synthesized compounds were also screened for their antibacterial activity against Staphylococcus aureus MTCC-96, Escherichia coli MTCC-443, Bacillus subtilis MTCC-441, Pseudomonas aeruginosa MTCC 1688, and antifungal activity against Aspergillus niger MTCC-282 and Penicillium sp. at different concentration and compared with standards drugs. The minimum inhibition concentration (MIC) of the compounds was studied by micro-broth dilution method.
Anilkumar S. Patel, Satishkumar D. Tala, Pankajkumar B. Nariya, Kartik D. Ladva, and Naval P. Kapuriya
Wiley
Mahesh M. Savant, Kartik D. Ladva, and Archna B. Pandit
Informa UK Limited
ABSTRACT A series of novel 3-amino-4,5-dihydro-6-methyl-4-oxo-N-aryl-1H-pyrazolo[4,3-c]pyridine-7-carboxamide have been synthesized starting from various oxoketene dithioacetals. The cyclocondensation reaction of 2-(bis(methylthio)methylene)-3-oxo-N-arylbutanamide 2a–w with cyanoacetamide using NaOiPr as base under reflux condition afforded novel highly functionalized pyridone 3a–w derivatives. Further, [3 + 2] cyclocondensation reaction of pyridones with hydrazine in the presence of alcohol was yielded pyrazolopyridones (23 nos) 4a–w with excellent yields. All newly synthesized compounds were evaluated for in vitro anti-HIV activity using MTT method. Most of these compounds have showed moderate to potent activity against HIV-1 (IIIB) and HIV-2 (ROD) strains with an IC50 ranging from >18 IC50[µg/ml] to <100 IC50[µg/ml]. Among them, compounds 4j and 4v were identified as the most promising compound for both types of HIV strains. (IC50 = 18 µg/ml). Three compounds 4l, 4m, and 4p have been found potent anti-HIV 1 and 2 activity against MT-4 cells. GRAPHICAL ABSTRACT
Archana B. Pandit, Mahesh M. Savant, and Kartik D. Ladva
Wiley
J. J. Travadi, M. S. Vadodaria, K. D. Ladva, and A. V. Doshi
Informa UK Limited
ABSTRACT A novel ester homologous series of liquid crystals with a highly polar laterally substituted –OCH3 group is synthesized and studied with a view to understanding and establishing the effects of molecular structure involving lateral substitution on liquid crystal behavior. The novel series RO·C6H4·COO·C6H3·OCH3(ortho)CH=CH·COO·C2H5 consists of 12 homologs of which C7, C8, C10 are nematogenic and C12, C14, C16 homologs are smectogenic. The rest of the homologs are nonliquid crystals. The textures of nematic phase are threaded and the smectic phase is of the type A or C. Transition temperatures and the textures of mesophases were determined by an optical polarizing microscope equipped with a heating stage. Analytical and spectral data support the molecular structures. The N-I and Sm-I transition curves behave in normal manner without exhibition of an odd-even effect. Average thermal stability for smectic and nematic are 127.3°C and 129°C, respectively. The total mesophase length ranges from 17°C to 57°C and series is of a middle ordered melting type with transition temperatures varying between 82°C and 148°C. The liquid crystal properties of present novel series are compared with, structurally similar known homologous series.
J. J. Travadi, M. S. Vadodaria, K. D. Ladva, and A. V. Doshi
Informa UK Limited
ABSTRACT A novel mesogenic ester homologous series is synthesized and studied with a view to understanding and establishing the effect of laterally substituted -OCH3 on mesomorphic behavior. The series consists of twelve members. C1 to C4 members are nonmesogenic, C6 to C12 are smectogenic in addition to nematogenic, and C14 to C16 are only smectogenic. The textures of smectic and nematic phases are A or C type and threaded or Schlieren, respectively. The transition curves in a phase diagram exhibit an odd–even effect and behave in normal manner except for the C14 and C16 derivatives in Sm-I transitions. Thermometric data were determined by an optical polarizing microscope equipped with a heating stage. Average thermal stability for smectic and nematic are 107.7°C and 121.0°C, respectively. Smectogenic and nematogenic mesophase length ranges from 11.0 to 44.0°C and 12.0°C to 39.0°C, respectively. The mesomorphic properties of present series are compared with structurally similar other known series. Thus, present series is predominantly smectogenic and partly nematogenic of middle ordered melting type.
J. J. Travadi, M. S. Vadodaria, K. D. Ladva, and A. V. Doshi
Informa UK Limited
ABSTRACT A novel homologous series of liquid crystal (LC) derivatives of general structure: RO·C6H4·COO·C6H3·OCH3(ortho)CH = CH·COO·(n)C5H11 was synthesized and studied with a view to understanding the effect of molecular structure on liquid crystal behavior with reference to lateral –OCH3 and terminal end group. Homologous series consists of 12 derivatives (C1–C16), the first five (C1–C5), and the last (C16) members are not liquid crystals and the rest of the homologs (C6–C14) are enantiotropically smectogenic without exhibition of the nematic phase. The textures of the smectic phases are focal conic fan shaped or batonets of smectic-A or smectic-C. Average thermal stability for smectic is 81.8°C and mesophase length ranges from 9°C to 31°C. Transition curves of a phase diagram (Sm-I and Cr-Sm/I) behave in a normal manner. The Sm-I transition curve exhibits an odd-even effect. Analytical and spectral data support the molecular structures. The series is smectogenic of a middle ordered melting type. LC properties of the present series are compared with structurally similar known homologous series. Transition temperatures were determined by an optical polarizing microscope equipped with a heating stage.
J. J. Travadi, M. S. Vadodaria, K. D. Ladva, and A. V. Doshi
Informa UK Limited
ABSTRACT A novel cinnamate ester homologous series has been synthesized and studied with a view to understanding and establishing the effects of molecular structure on liquid crystal (LC) properties with a focus on the highly polar methoxy group as a lateral substituent. The series consists of twelve homologs; of which C1–C5 are nonmesogenic, and the rest of the homologs are enantiotropically smectogenic or and nematogenic. The texture of nematic phases is threaded or Schlieren and that of the smectic is either smectic A or C, as recognized and determined through an optical polarizing microscope equipped with a heating stage. The Sm-N I and N-I transition curves exhibit odd-even effects and behave in normal manner. The Cr-I M behaves in normal manner. Analytical and spectral data confirm the molecular structures of homologs. The average thermal stabilities for smectic and nematic are 125.3 C and 129.8 C, respectively, whose total mesophase length varies from 13 C to 51 C. Some LC properties of present series are compared with the structurally similar known series.
M. S. Vadodaria, K. D. Ladva, A. V. Doshi, and J. J. Travadi
Informa UK Limited
ABSTRACT A novel ester homologous series was synthesized and studied with a view to understanding and establishing the effects of molecular structure on liquid crystal properties with a common laterally substituted –OCH3 group and changing terminal groups. The novel series consists of twelve members. The C1 to C3 members are not liquid crystals and the rest of the members C4 to C16 are smectogenic without exhibition of nematic character. Textures of smectic phase are focal conic fan shaped of the type A or C. The transition temperatures and textures of smectic mesophases were observed through hot stage polarizing microscopy (POM). The transition curves (Cr-I or Cr-M and Sm-I) behaved in normal manner. Analytical and spectral data support the molecular structures. Average thermal stability for smectic is 77.25°C and smectogenic mesophase ranges from 15°C to 33°C. Liquid crystal properties of the present series are compared with structurally similar homologous series. Thus, the series is smectogenic only with three homologs nonmesogenic.
M. S. Vadodaria, K. D. Ladva, A. V. Doshi, and J. J. Travadi
Informa UK Limited
ABSTRACT Novel liquid crystal (LC) materials of ester derivatives were synthesized and studied with a view to understanding and establishing the effects of molecular structure on LC properties. The novel molecules consist of two phenyl rings bonded through –COO– central group and a laterally substituted methoxy group with –OCnH2n+1 as well as –COOCH3 terminal end groups, and yielded 12 homologous members of an ester series. The C1 to C3 members are nonmesomorphic, the C4 to C12 members are enantiotropic nematic only, and the C14 to C16 members are enantiotropically smectogenic in addition to nematogenic. Transition temperatures and the textures of LC state were observed through an optical polarizing microscope (POM) equipped with a heating stage. The textures of nematic phase are threaded or Schlieren, and that of smectic phase are focal conic of the type A or C. Transition curves of a phase diagram behave in normal manner with the exhibition of an odd-even effect (only N-I). Analytical and spectral data support the molecular structures of the novel ester derivatives. The LC properties of the present series are compared with structurally similar other known series. The average thermal stability of the series is 93°C for smectic and 120.88°C for nematic and the mesogenic phase length ranges between 2°C and 46°C.
J. J. Travadi, M. S. Vadodaria, K. D. Ladva, and A. V. Doshi
Informa UK Limited
ABSTRACT A novel homologous series of esters with a lateral methoxy group and terminal n-heptyl cinnamate group was synthesized and studied to investigate mesomorphic behavior in relation to structure. The twelve membered series consists of methoxy to pentyloxy derivatives that are nonmesomorphic and the rest of the homologs as smectegenically mesomorphic, including C6 and C7 monotropic smectic and C8 to C16 enantiotropic smectic without exhibition of any nematic property. The textures of smectogenic mesophases are focal conic fan shaped or batonates of the type smectic-A or Schlieren-C. An odd-even effect is exhibited by the Sm–I transition curve in the phase diagram. The Cr–Sm and Sm-I transition curves behave in a normal manner. Transition temperatures and textures were determined on an optical polarizing microscope, equipped with a heating stage. Some representative members were characterized by IR, H1NMR, mass spectra, and elemental analysis. Analytical data support the molecular structures of the homologs. Mesomorphic properties of the present novel series are compared with the structurally similar known series. The present series is smectogenic only, whose thermal average stability is 89.8°C and of a middle-ordered melting type.
Kamini Kapoor, Vivek K. Gupta, Rajni Kant, Poorvesh M. Vyas, Mihir J. Joshi, Kalpesh M. Menpara, and Kartik D. Ladva
International Union of Crystallography (IUCr)
In the chromenothiazole ring system of the title molecule, C20H25N3O2S, the pyran ring is in a half-chair conformation. The dihedral angle between the thiazole and benzene rings is 14.78 (6)°. The cyclohexane ring is in a chair conformation. The crystal structure is stabilized by weak intermolecular C—H⋯N and C—H⋯O hydrogen bonds.
Samir Vyas, Ajay Patel, KartikD Ladva, HS Joshi, and AtulH Bapodra
Medknow
Omeprazole is widely prescribed in the form of enteric-coated formulations, due to the rapid degradation of the drug in the acidic condition of the stomach. In the current article, we are reporting the development and complete validation of a stability indicating chiral high-performance liquid chromatography (HPLC) method for the enantioselective analysis of omeprazole in the enteric-coated formulations. A precise and sensitive enantiomeric separation of omeprazole was obtained on Chiralcel OD-H analytical column (250mm × 4.6 mm, 5μm particle size) using normal phase chromatography. The analysis was performed under UV detection at 301nm wavelength. During method development, the addition of methanol to the mobile phase helped in getting the sharp peaks. The developed method showed linear response over a wide concentration range of 0.39-800μg/ml and the regression coefficients value (r2) was obtained more than 0.999 for (S)- and (R)-omeprazole. The lower limit of detection (LLOD) and lower limit of quantification (LLOQ) for (R)-omeprazole were found to be 0.39 and 0.78 μg/ml, respectively for 5 μl injection volume. The percentage recovery of (R)-omeprazole ranged from 93.5 to 104 in spiked formulation samples and omeprazole sample solution and mobile phase were found to be stable for at least 24 h at room temperature. The proposed method was found to be suitable and accurate for the quantitative determination of undesired enantiomer in the enteric-coated omeprazole formulations.