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"Ligan 2-(1,5-difenil-4,5-dihidro-1H pirazol-3-yl)piridin telah berhasil disintesis dengan metode Ciupa dkk. (2012). Reaksi yang berlangsung dalam sintesis ligan berbasis pirazolin ini merupakan reaksi kondensasi aldol dan Reduksi Wolff-kishner. Hasil yang diperoleh berupa padatan jingga dengan %yield sebesar 19,91% (0,2987 gram). Ligan 2-(1,5-difenil-4,5-dihidro-1H pirazol-3-yl)piridin ini dilakukan uji karakterisasi terhadap spektrofotometer IR, H-NMR, spektrofotometer UV-Vis dan spektrofluorofotometer. Struktur kompleks yang terbentuk dari ketiga logam tersebut adalah struktur segi empat planar dengan rumus seyawa kompleks [CuL2]2+ [CdL2]2+ dan [PbL2]2+. Aplikasi pada penelitian ini yaitu fluorosensor ligan terhadap ion logam berat berat Cu2+, Cd2+ dan Pb2+. Dengan adanya penambahan ion logam berat Cu2+ dan Pb2+ memberikan fluorosensor tipe on-off terlihat dari adanya pemadaman intensitas fluoresensi dan fluorosensor tipe off-on untuk ion logam berat Cd2+ yang ditandai dengan peningkatan intensitas fluoresensi. Ligan ini dapat mendeteksi ion logam berat dari 2x10-4 M hingga konsentrasi 2x10-6 M memiliki keselektifan terhadap ion logam berat Cd2+.

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Ligand 2-(1,5-difenil-4,5-dihidro-1H pirazol-3-yl)piridin has been synthesized by Ciupa et al. (2013) method. The synthesis used aldol condensation reaction and Wolff-kishner reduction. The orange precipitated was collected and gave 19,91% yield 0,2987 gram). Ligand has been characterized by FTIR, H-NMR, UV-vis and Spectrofluorophotometer. The structur of the complex formed from the third metal is square planar with formula of complex are [CuL2]2+ [CdL2]2+ dan [PbL2]2+.

The application in this research is fluorosensor of heavy metal ions Cu2+, Cd2+ dan Pb2+. With the addition of heavy metal ions Cu2+ and Pb2+ that ligand gave fluorosensor type on-off. It conclude by quenching when ligand coordinated with Cu 2+ and Pb 2+ ions. And ligand gave fluorosensor type off-on when addition of heavy metal ion Cd2+. These ligan can detect of heavy metal ions from 2x10-4 M to a concentration of 2x10-6. It conclude by enhanching when ligand coordination with Cd2+ ion and the ligand have selectivity towards Cd2+."

"Sorbitan ester asam lemak merupakan surfaktan hasil esterifikasi sorbitan dengan asam lemak. Sorbitan stearat dan sorbitan oleat merupakan senyawa non-polar dan memiki gugus hidroksi sehingga berpotensi sebagai pengikat ion logam. Pada penelitian ini, disintesis sorbitan stearat dan sorbitan oleat dari sorbitol menggunakan katalis H2SO4 dan NaOH serta aplikasinya sebagai ligan terhadap ion logam Zn2 dan Pb2 pada sampel sludge Tegal. Sintesis sorbitan ester dilakukan melalui tahap dehidrasi dan tahap esterifikasi. Sorbitan ester hasil sintesis dikarakterisasi dengan FTIR dan ditentukan kadar asam lemak bebasnya. Studi pembentukan kompleks dilakukan dengan metode job menggunakan spektrofotometer UV-Vis. Konsentrasi ion logam yang terikat oleh ligan dianalisis menggunakan AAS. Sorbitan ester hasil sintesis diaplikasikan terhadap hasil destruksi basah sampel sludge Tegal dengan variasi pH dan volume larutan. Melalui penelitian ini berhasil disintesis sorbitan stearat dan sorbitan oleat dengan nilai asam 29,45 mg/g dan 65,92 mg/g serta kadar asam lemak bebas sebesar 14,94 dan 33,19 . Sorbitan stearat hasil sintesis memiliki kemampuan dalam mengikat ion logam yang paling baik dibandingkan sorbitan oleat dan Span 80 yaitu mampu mengikat 30,5 ion Zn2 dan 42 ion Pb2 dari larutan destruksi sampel sludge Tegal dengan waktu kontak 2 s, pH 1 dan perbandingan volume logam : ligan sebesar 2 : 1.

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Sorbitan fatty acid ester is a surfactant made from esterification reaction of sorbitan and fatty acid. Sorbitan stearate and sorbitan oleate have a potential as metal ligand due to their hydroxyl groups and because of their non polar properties. In this research, synthesis of sorbitan stearate and sorbitan oleate were carried out using sorbitol and catalyzed by H2SO4 and NaOH. Synthesis of both sorbitan esters were done in two steps, the first step was dehydration of sorbitol and then esterification. The products of the reaction were characterized using FTIR and the acid values were also evaluated. Later on, the sorbitan esters ability to bind with metal ions was studied using AAS to analyze the concentration of metal ion solution. The complex formation study was done with Job`s Method using UV Vis spectrophotometers. We also studied the use of sorbitan esters as ligand for metal ions in solution of industrial sludge from Tegal. The sorbitan ester products has acid values of 25,45 mg g and 65,9 mg g for sorbitan stearate and sorbitan oleate respectfully, with 14,94 and 33,19 free fatty acids. Compared to sorbitan oleate and Span 80, the sorbitan stearate product has the best potential to be use as ligand, as it can bind up to 30,5 of Zn2 ion and 42 of Pb2 ion from destruction solution of Tegal`s industrial sludge with the optimum condition contact time 2 s, pH 1, and metal ligand volume ratio is 2 1."

"G protein-coupled receptors (GPCRs) are one of the most important target classes in pharmacology and are the target of many blockbuster drugs. Yet only with the recent elucidation of the rhodopsin structure have these receptors become amenable to a rational drug design.Based on recent examples from academia and the pharmaceutical industry, this book demonstrates how to apply the whole range of bioinformatics, chemoinformatics and molecular modeling tools to the rational design of novel drugs targeting GPCRs."

"The lock-and-key principle formulated by Emil Fischer as early as the end of the 19th century has still not lost any of its significance for the life sciences. The basic aspects of ligand-protein interaction may be summarized under the term 'molecular recognition' and concern the specificity as well as stability of ligand binding. Molecular recognition is thus a central topic in the development of active substances, since stability and specificity determine whether a substance can be used as a drug. Nowadays, computer-aided prediction and intelligent molecular design make a large contribution to the constant search for, e. g., improved enzyme inhibitors, and new concepts such as that of pharmacophores are being developed."

"Salah satu metode untuk menentukan keberadaan ion logam dalam suatu sampel adalah dengan senyawa pengkelat yang mampu berfluorosensi dalam bentuk kompleksnya. Senyawa ligan pengkelat yang dimanfaatkan dalam penelitian ini adalah ligan 2-(1-metil-5-fenil-4,5-dihidro-1H-pirazol-3-yl)piridin. Senyawa ligan tersebut disintesis dengan dua tahap yakni tahap kondensasi Claisen-Schmidt dan tahap penambahan metil hidrazin berlebih. Karakterisasi senyawa ligan yang disintesis dilakukan dengan bantuan instrumentasi seperti spektroskopi FTIR dan NMR. Eksperimen ini bertujuan untuk mempelajari pengaruh konsentrasi ion logam Cu2+ dan Fe3+ yang dikelatkan dengan ligan 2-(1-metil-5-fenil-4,5-dihidro-1H-pirazol-3-yl)piridin, terhadap kemampuannya berfluorosensi sebagai senyawa kompleks. Selektivitas ligan dalam mengkelat ion logam-pun dipertimbangkan. Variasi konsentrasi kedua ion logam diurutkan dari 0,001; 0,002; 0,003; 0,004; 0,005; 0,006; 0,007; 0,008; 0,009 dan 0,01 mol L-1, dalam keberadaan 0,01 mol L-1 senyawa ligan. Dari hasil penelitian ini, ditemukan bahwa seiring peningkatan konsentrasi ion Cu2+ pada kompleks Cu-ligan, emisi fluorosensinya semakin meredup, pada panjang gelombang 255 nm. Hal yang sama terjadi pada kompleks Fe-ligan, terjadi peredupan emisi seiring dengan meningkatnya konsentrasi Fe3+ pada kompleks Fe-ligan, di atas konsentrasi Fe3+ 0,028 mol L-1, pada panjang gelombang 509 nm. Pada uji selektivitasnya, tercatat bahwa ligan ligan 2-(1-metil-5-fenil-4,5-dihidro-1H-pirazol-3-yl)piridin lebih senang mengkelat ion Fe3+ dibandingkan Cu2+.

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One of the method to determine the presence of metal ions in a certain sample, is by using a chelating ligand that gives fluorescent emission when forming it?s complex compound. The ligand compound utilized in this experiment is 2-(1-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)pyridine. The organic ligand was synthesized using a two-step reaction: the first step is a Claisen-Schmidt condensation reaction, the second step is the addition of excess methyl hydrazine. Characterization of the ligand synthesized in this experiment, was done by using instruments such as FTIR spectroscopy and NMR. This experiment was to study the effect of Cu2+ and Fe3+ concentrations that were chelatet by 2-(1-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)pyridine ligand, on the fluorescent abilities of their respective complex compounds.

The selectivity of the ligand on chelating the two metal ions, was also taken to account. The concentration of both metal ions were varied from 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009 dan 0.01 mol L-1, in the presence of 0.01 mol L-1 ligand. From the experimental results, it is shown that as the concentration of Cu2+ increased in Cu-ligand complex, the fluorescent emission became dimmer, at wavelength 385 nm. The same thing happened with Fe-ligand complex, the fluroscent emission of Fe-ligand became dimmer as the concentration increased, at wavelength 509 nm. In the selectivity test, it was shown that 2-(1-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)pyridine ligand was more favorable to chelate Fe3+ ions instead of Cu2+."

"With increasing use of ligand-binding assays (LBAs) in the pharmaceutical industry, the need to critically evaluate technical and regulatory issues related to the use of these technologies has increased greatly. This book fills that void and provides a reference text covering critical aspects of the development, validation, and implementation of LBAs in the drug development field. It includes: immunochemistry and protein chemistry, method development, validation, statistics, software, regulatory issues, and applications to immunogenicity and biomarkers. "

"The book includes : structural, physical, and chemical properties of fluorous compounds, selective fluoroalkylation of organic compounds by tackling the negative fluorine effect, synthetic and biological applications of fluorous reagents as phase tags, chemical applications of fluorous reagents and scavengers, and more. "

"Carola Vogel’s PhD thesis focuses on the synthesis, and structural and spectroscopic characterization of the first high valent iron nitride complexes. In her interdisciplinary and collaborative research Carola also describes the reactivity studies of a unique iron (V) nitride complex with water. These studies show that quantitative yields of ammonia are given at ambient conditions. High valent iron nitride and oxo species have been proposed as key intermediates in many bio-catalytic transformations, but until now these species have proven exceedingly challenging to isolate and study. Iron complexes in high oxidation states can thus serve as models for iron-containing enzymes to help us understand biological systems or aid our development of more efficient industrial catalysts."