Hans-René Bjørsvik

Hans-René Bjørsvik
University of Bergen | UiB · Department of Chemistry

Ph.D., M.Sc.
Professor of Chemistry - Organic Synthesis & Medicinal Chemistry

About

118
Publications
9,571
Reads
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1,920
Citations
Citations since 2017
22 Research Items
642 Citations
2017201820192020202120222023020406080100
2017201820192020202120222023020406080100
2017201820192020202120222023020406080100
2017201820192020202120222023020406080100
Additional affiliations
May 2002 - present
University of Bergen
Position
  • Professor (Full)
August 1999 - April 2002
University of Bergen
Position
  • Professor (Associate)
August 1994 - July 1998
Politecnico di Milano
Position
  • Visitining senior research scientist

Publications

Publications (118)
Article
Metastatic tumors with moderate radiosensitivity account for most cancer-related deaths, highlighting the limitations of current radiotherapy regimens. The xCT-inhibitor sulfasalazine (SAS) sensitizes cancer cells by blocking xCT-mediated cystine uptake, and thereby glutathione (GSH) synthesis protecting against radiation-induced oxidative stress....
Article
A selective and high-rate Ru-catalyzedcross-metathesis reaction of alkenes with vinylimidazole is disclosed. Cross-metathesis is known to operate less efficiently on N-heterocycles, but through optimization by means of statistical experimental design and multiple regression, optimal reaction conditions were identified that allowed for consistent hi...
Article
Full-text available
A high rate, selective, and productive Appel type reaction was developed. The method allows for ipso-substitution of the alcoholic hydroxy group with halogens ∈ [ Cl, Br, I]. The method demands mild reaction conditions that includes very short reaction time, <15 min. only versus 1-2 days using the classical Appel reaction conditions. The method was...
Article
Full-text available
Metastatic tumors with moderate radiosensitivity account for most cancer-related deaths, highlighting the limitations of current radiotherapy regimens. The xCT-inhibitor sulfasalazine (SAS) sensitizes cancer cells to radiotherapy by blocking cystine uptake via the xCT membrane antiporter, and thereby glutathione (GSH) synthesis protecting against r...
Poster
BACKGROUND Although withdrawn from the market due to cardiotoxicity, we showed that the antipsychotic drug Thioridazine shows chemosensitizing effects in combination with Temozolomide (TMZ) for the treatment of glioblastoma multiforme (GBM). Based on our prior observations, the aim of this study was through medicinal chemistry, to design and synthe...
Poster
BACKGROUND Although withdrawn from the market due to cardiotoxicity, we have shown that the antipsychotic drug Thioridazine shows chemosensitizing effects in combination with Temozolomide (TMZ) for the treatment of glioblastoma multiforme (GBM). Based on our prior observations, the aim of the presented project was through medicinal chemistry, to de...
Article
Full-text available
The Front Cover shows some of the xCT inhibitor molecule candidates that were synthesised through a structure–activity relationship study, in which each candidate molecule was evaluated for its capability to inhibit the xCT antiporter (the blue‐coloured gate) that leads into the orange‐coloured cell. A successful xCT inhibitor candidate operates as...
Article
A selective oxidative Heck cross‐coupling method was developed and optimized as a pivotal step for a synthetic route leading to the trans‐ stilbene framework. The developed method and synthesis were needed in a SAR study in progress that concerned design and development of an inhibitor for the human cell xCT antiporter system. The developed oxidati...
Article
Full-text available
The xCT antiporter is a cell membrane protein involved in active counter-transportation of glutamate (outflux) with cystine (influx) over the human cell membrane. This feature makes the xCT antiporter a crucial element of the biosynthesis of the vital free radical scavenger glutathione. The prodrug sulfasalazine, a medication for the treatment of u...
Patent
The present invention relates to the treatment of leukemia. In particular, it relates to the use of compounds based on a 2-amino-[1,1']-biphenyl or corresponding carbazole scaffold and derivatives thereof, in such treatment.
Patent
The present invention relates to the field of cancer treatment More specifically, the invention relates to the use of certain compounds as radiosenzitizers in combination with radiation treatments eatment of cancer. Such combination therapy is particularly suitable for the treatment of cancer such as glioblastomas which are lethal cancers and inher...
Article
Full-text available
A general and selective Pd‐catalyzed cross‐coupling of aromatic boronic acids with vinylimidazoles is disclosed. Unlike most cross‐coupling reactions, this method operates well in absence of bases avoiding the formation of by‐products. The reactivity is highly enhanced by the presence of nitrogen‐based ligands, in particular bathocuproine. The meth...
Article
A series of N‐ aryl and N‐ alkyl substituted imidazoles were synthesized and complexed with Ag + to obtain silver‐NHC complexes of the form [Ag(NHC)2 ]X. These silver‐NHC complexes were tested in‐vitro versus the human cell lines HL‐60 and MOLM‐13 that both model acute myeloid leukemia (AML). A substantial difference in cytotoxicity was revealed va...
Article
A previously designed and developed twelve‐step total synthesis that includes [1,1'‐biphenyl]‐2‐amine and carbazole intermediates that ultimately produces the carbazole alkaloid carbazomycin G was exploited as a screening compound library with the goal to identify potential lead compound(s) with cytotoxic effect. These compounds were investigated u...
Article
Primary and benzylic alcohols were cost-effectively transformed into their corresponding nitriles using classical batch and a continuous flow process implemented on a multi-jet oscillating disk (MJOD) reactor platform. The alcohol as substrate was treated with (2,2,6,6-tetra-methylpiperidin-1-yl)oxidanyl free radical (TEMPO) as a pre-catalyst with...
Article
An efficient and easy recyclable heterogeneous oxidation catalyst was prepared by grafting TEMPO–NH2 moieties on the surface of magnetic multi walled carbon nanotubes (MWCNT), first by a radical reaction introducing butyric acid moieties on carbon nanotube surface. Subsequently, carboxylic acid moieties were submitted for amidation using TEMPO–NH2....
Article
A three step continuous-flow process leading to the fungicide Boscalid® is disclosed. The first step of the process is a Suzuki cross-coupling where 1-chloro-2-nitrobenzene is coupled with 4-chlorophenylboronic acid at a temperature of 80 oC using a solvent mixture of ethanol/water as reaction medium with sodium carbonate as base and tetrakis(triph...
Article
The amide bond formation constitute a reaction of paramount importance in organic synthesis, both within academic research and industrial development and manufacturing of pharmaceutical chemicals and other biologically active compounds. Despite this fact, as well as the ever‐increasing treatment costs of side streams and other environmental concern...
Article
A novel total synthesis leading to the carbazole alkaloid carbazomycin G was designed and developed. The outlined synthetic route is composed of twelve synthetic steps including the transformations of the initial simple substrate and intermediates. To realize the designed synthesis, in total six new synthetic methods were developed and implemented...
Article
A high yielding and high rate reduction method that operates with alkenes, alkynes, azides, nitriles, and nitroarenes was developed and optimized. The method makes use of sodium borohydride reduction of CoSO₄ under release of hydrogen along with the formation of Co₂B as a nanoparticle material. The protocol was proven to operate with an assortment...
Article
A new two-step synthetic process for the preparation of unsymmetrically substituted benzo[c]cinnolines was developed. The key intermediate 2,2’-dinitro-1,1’-biphenyl was prepared by means of an unprecedented tailored Suzuki cross-coupling protocol. The subsequent step is constituted by a domino partial nitro group reduction and intramolecular diazo...
Article
An efficient synthetic method for the synthesis of the carbazole scaffold was designed and investigated. The method was developed to produce substituted carbazoles by an intramolecular combination of a free amine group and an arene. The steps of the method involves a concurrent Pd catalysed C−H activation and intramolecular C-N bond formation. The...
Article
A batch synthesis to the iodinating agent 1,3-diiodo-5,5-dimethyl-imidazolidine-2,4-dione (DIH) was de- vised and developed. This batch process was then up-scaled (10×) and optimized by means of statistical experimental design and multivariate regression. The optimized batch procedure was then transferred and adapted for continuous flow synthesis u...
Article
Flow processes for mono- and di-iodination of the imidazole backbone were devised, developed, and implemented on the multi-jet oscillating disk (MJOD) flow reactor platform. The flow processes were based on batch protocols previously developed in our research group and involved N,N′-1,3-diiodo-5,5- dimethylhydantoin as the iodination reagent. The f...
Article
The simple In-based protocol for the reduction of 2-nitrobiphenyls tolerates a variety of functional groups and gives high yields of the target 2-amino derivatives.
Article
An improved and simplified In-based protocol for the reduction of 2-nitro-1,1’-biphenyls to the corresponding 2-amino-1,1’-biphenyls is disclosed. The method utilises only a stoichiometric quantity of indium powder as the reducing reagent along with a stoichiometric quantity of ammonium chloride. The work-up is very simple, it requires only a simpl...
Article
A simple and efficient method for Suzuki cross-coupling of highly substituted and congested 1-chloro-2-nitrobenzene with phenylboronic acid was developed, investigated, and optimized. The reaction conditions comprises a mixture of MeOH and water (4:1) as the reaction medium, readily available and cheap Pd(PPh3)4 as catalyst, sodium carbonate as bas...
Article
The inside cover picture shows two silver–N-heterocyclic carbene (NHC) complexes with different alkyl side chains at the 4-position, namely NHC-1 (methyl, orange) and NHC-2 (heptyl, green). To accomplish the devised de novo total synthesis, we utilized novel and indispensable synthetic methods recently developed by our group. Both complexes exhibit...
Article
Full-text available
Computational chemistry has shown that backbone-alkylated imidazoles ought to be efficient ligands for transition metal catalysts with improved carbene-to-metal donation. In this work, such alkylated imidazoles were synthesized and complexed with silver(I) by means of an eight/nine-step synthetic pathway we devised to access a new class of biologic...
Article
Peroxy acids can be used as the terminal oxidant for the Baeyer–Villiger oxidation of acetophenones and for direct ring hydroxylation of methoxy-substituted benzenes. An oxidative system involving 3-chloroperbenzoic acid (mCPBA) and 2,6-dimethoxyacetophenone as model substrate was investigated by means of statistical experimental design, multivaria...
Article
A Sonogashira coupling reaction method to join terminal alk- ynes to the imidazole backbone was developed and investi- gated. The method exhibits good functional group tolerance and provides target 4-alkynylated imidazoles in 70–93% yield. The alkyne reagents were characterized by means of DFT calculations, from which electrostatic potential surfac...
Article
A two-way switchable Pd-catalyzed process that can pursue two different mechanisms, namely hydro- and methoxy-deiodi- nation was discovered, developed, and optimized by means of statistical experimental design, multivariate modelling, and re- sponse surface methodology. The investigation revealed that the two-way switchable process might be control...
Article
We have revisited the Stille coupling reaction for the functionalization of the imidazole backbone. In this context CuI was exploited as a co-catalyst, which resulted in significantly improved yields of target coupling products. Furthermore, a systematic investigation of the effect of the auxiliary group on the N-1-ring atom was performed. When mon...
Article
A number of secondary metabolites resembling a polysubstituted 2-aminoimidazole scaffold are found in a variety of marine sponges. Due to the diversity in the biological activity with drug-like properties, several research groups have designed and developed strategies and syntheses leading to these marine alkaloids. This report constitutes a summar...
Article
The multijet oscillating disk (MJOD) flow reactor is a relatively new technology for continuous flow synthesis. This technology is still under investigation as an all-round platform for flow synthesis. In this article, findings are disclosed from a project where a MJOD flow reactor rig (reactor volume of ≈50 mL) was investigated as the reaction pla...
Article
3,3,4,4-Tetraethoxybut-1-yne (TEB) is a versatile synthon that can be produced in a four-step synthesis. The third step of the synthesis is a cycloproanation, which has been thoroughly investigated and optimized by means of statistical experimental design and multivariate modeling. At the outset, an exhaustively pre-experimental design was performe...
Article
The Suzuki reaction of 4,5-A three-way switchable Pd-catalyzed and microwave assisted process appropriate for selective arylation or hydrodehalogenation of the imidazole backbone was discovered and entirely optimized. The “arylation switch position” was adapted and op- timized for the synthesis of 4,5-diaryl-1H-imidazoles, while the “hydrodehalogen...
Article
A three-way switchable Pd-catalyzed and microwave assisted process appropriate for selective arylation or hydrodehalogenation of the imidazole backbone was discovered and entirely optimized. The "arylation switch position" was adapted and optimized for the synthesis of 4,5-diaryl-1H-imidazoles, while the "hydrodehalogenation switch position" was us...
Article
An instantaneous, selective and high-yielding halogenation process is reported. The method operates with imidazoles, pyrazoles, and indoles under benign reaction conditions. The developed process involves the use of N,N′-dihalo-5,5-dimethylhydantoins (halo=chlorine, bromine, iodine) as halogenation reagents that are activated by catalytic quantitie...
Article
The development of a multivariate study for a quantitative analysis of six different polybrominated diphenyl ethers (PBDEs) in tissue of Atlantic Salmo salar L. is reported. An extraction, isolation, and purification process based on an accelerated solvent extraction system was designed, investigated, and optimized by means of statistical experimen...
Article
A multijet oscillating disk (MJOD) millireactor system suitable for operating at cryogenic temperatures has been developed, assembled, and investigated. This new reactor system (cryoMJOD) was realized with the purpose to prepare various phenylboronic acids in a continuous two (three)-step telescoped synthetic process at temperatures in the interval...
Article
The times are changing: A batch process, the Minisci epoxidation, is transformed into a continuous-flow protocol for the selective aerobic radical epoxidation of alkenes. The use of a novel reactor type allows to considerably shorten reactor residence times. Experimental results suggest that two different reaction mechanisms exist for the oxidation...
Article
Organic solvent nanofiltration (OSN) is a recently commercialized technology, which we have used to develop a method for the separation of a target product and the Pd catalyst from a Heck coupling postreaction mixture. The experimental setup included commercially available polyimide copolymer membranes with molecular weight cut-off (MWCO) values in...
Article
This report discloses proof of concept and experimental results from a project involving design, development, and investigation of a novel approach for flow chemistry and the realization of equipment operating according to this new approach. This device is named multijet oscillating disk (MJOD) reactor and is dedicated to continuous flow organic sy...
Article
An environmentally benign, convenient, high yielding, and cost-effective synthesis leading to idebenone is disclosed. The synthesis includes a bromination process for the preparation of 2-bromo-3,4,5-trimethoxy-1-methylbenzene, a protocol for the Heck cross-coupling reaction using either thermal or microwave heating, olefin reduction by palladium c...
Patent
A method is described for the preservation of oxidation of components in an oil, where berries or fruit are crushed to a pulp of berries and that the pulp of berries is then pressed for the separation into two phases, a juice phase and a press residue, and. that the press residue is added to an oil exposed to oxidation. Also described is met to red...
Article
The mechanism and the synthetic applications for the oxidation of alcohols, ethers, and aldehydes by H2O2 catalyzed by Bf2 or Br- in a liquid two-phase system (aqueous and organic) are reported. Aliphatic and benzylic primary alcohols and ethers show an opposite behavior, which has been rationalized on the ground of the different electronic configu...
Article
A multivariate design and optimization study for the synthesis of the bromoalkanol 10-bromo-1-decanol using decane-1,10-diol as substrate is reported. The bromination process was supported by the phase transfer catalyst tetrabutylammonium bromide with aqueous HBr (48%) as the brominating reagent. The optimized batch protocol provided a yield of 64%...
Article
An efficient high-yielding and environmentally benign switchable oxidation process that can selectively produce two different versatile synthetic intermediates is disclosed. One of the two intermediates, 2,3-dimethoxy-5-methylcyclohexa-2,5-diene-1,4-di-one (coenzyme Q 0), is obtained by means of a telescoped two-step synthetic protocol that in the...
Article
A new sterically demanding bidentate imidazolium bromide has been prepared and used as ligand precursor for the synthesis of the corresponding NHC–silver(I) complex. The X-ray analysis of the silver(I) complex revealed a rare Ag4O4 core cubane cluster. The silver(I) complex reacts readily with the Grubbs first generation catalyst providing a labile...
Patent
The present invention discloses a new process for the preparation of 1,4-benzoquinones.of formula (II), wherein R1, R2, R3, and R4 are independently selected form the group consisting of branched or unbranded C1-C6 alkyl, phenyl, and benzyl, wherein phenyl and benzyl is optionally substituted by one or more substituent independently selected from t...
Article
An efficient, high yielding, and environmentally benign bromination using an alkali metal bromide as the bromine source is disclosed. Investigation of the protocol revealed that the method operates for activated arenes producing the corresponding monobrominated products in good to excellent yields.
Article
A density functional theory-based computational comparison of various [Ru]−L bonds in L(PCy3)Cl2RuCH2 complexes, where L is a dative ligand, shows that similar bond strengths can be expected for ruthenium−imine and ruthenium−amine bonds. The similarity remains when comparing the corresponding bond strengths in ruthenium olefin metathesis catalysts...
Article
A ruthenium complex coordinated by a bidentate aryloxy-NHC ligand has offered the first example of an imidazolium-substituted metal alkylidene, an analogue of existing phosphonium alkylidenes and metal-substituted ketenes. Investigation of the molecular structure and the quantum chemically obtained electronic structure sheds light on the nature of...
Patent
A.reactor is described for conversion of chemical reactants comprising an oscillator with a number of perforated discs. The reactor is also suited to continuous conversion of reactants, and a method for such conversion is also described.
Article
A simple, green synthetic protocol to bidentate Schiff base substituted ruthenium carbene complexes is described. These complexes are potent catalysts for olefin metathesis, but the original synthetic route employs the Schiff base ligands in the form of highly toxic thallium(I) salts. The new protocol involves a two-step, quasi-one-pot approach and...
Article
A quantitative structure-activity relationship (QSAR) model is presented in which both the independent and dependent (response) variables are derived from density functional theory (DFT) calculations on a large set of 14-electron complexes, LCl(2)Ru=CH(2), with different dative ligands, L. The multivariate model thus correlates the properties of th...
Article
A telescoped process for the preparation of 2-methoxy-3-methyl-[1,4]benzoquinone is disclosed. When this novel process is compared to the prevailing method that utilizes Na2Cr2O7 as the oxidant, the novel process represents a high yielding (95%), green, and environmentally benign alternative with H2O2 and HNO3 as the oxidants and CH3COOH as the rea...
Article
[Reaction: see text]. Mechanistic investigations and protocols for the synthesis of 2-nitrobiphenyls and 2,2'-dinitrobiphenyls are disclosed. It is revealed that obstacles appear during the transmetalation step when the phenylboronic acid is substituted with a nitro group in the 2-position, whereas when substituted in the 3- or 4-positions, the rea...
Article
[reaction: see text] A novel benign protocol for the preparation of hydroxy-methoxybenzene derivatives is disclosed. By utilizing this protocol, activated aromatic compounds such as 1,3-dimethoxy-2-methyl-benzene and 1-(2,6-dimethoxyphenyl)ethanone are smoothly converted to the corresponding monohydroxylated compound. The reaction can be considered...
Article
A novel deoxygenation process for N-heteroarene N-oxides is described. The deoxygenation process has been carried out by utilizing some short C-chain alcohols, benzyl alcohol, or 1-phenylethanol as the solvent in the presence of a base, such as sodium alkoxide or sodium hydroxide. A series of N-heteroarene N-oxides was submitted to the developed co...
Article
A new catalytic oxidation method for the preparation of aromatic carboxylic acids from methyl aryl ketones is reported. The method is an alternative to the haloform reaction; it is benign and affords the desired product without production of any harmful side products. The catalytic cycle is based on the use of an electron-deficient nitroarene as ca...
Article
A novel synthetic process leading to the framework of benzo[c]cinnoline has been discovered and investigated. The process is composed of two separate reactions, the first of which is a partial reduction of the nitro groups of the 2,2'-dinitrobiphenyl, a process that we believe proceeds via a SET mechanism to yield the hydroxyamino and nitroso group...
Article
Multivariate modeling and spectroscopy taken together constitute a powerful tool applicable to both process monitoring and to process and reaction optimizing. The present article establishes how near-IR spectroscopy utilizing a fiber-optical transmission probe can be combined with principal component analysis to extract concentration profiles from...
Article
A versatile and simple method for aerobic oxidation of various aromatics containing an oxygen-functionalized benzylic carbon is reported. Results from oxidation experiments with methyl aryl ketones, benzaldehydes, benzylic alcohols, and mandelic acid are reported; all provide high yields of the corresponding aromatic carboxylic acids. By means of r...
Article
A new aerobic oxidation method for conversion of methyl aryl ketones to the corresponding benzoic acids is presented. The method is cheap and environmentally friendly, which also makes it suitable for large scale industrial use. The method affords a yield of >75% with an almost 100% selectivity. Experiments have shown that the process operates foll...
Article
An efficient and convenient method has been developed for the oxidation of aryl alkyl and cyclopropyl alkyl ketones to aromatic and cyclopropane carboxylic acids by molecular oxygen at atmospheric pressure, catalysed by Mn(NQ 3) 2 in combination with Co(NO 3) 2 or Cu(NO 3) 2. This simple, cheap and highly selective process has a general character f...
Article
This is a general overview of some first-, second- and third-generation fine chemicals with origins from the lignin oxidation process. The synthetic organic processes of these substances are presented as well as several applications for the synthesis of a variety of pharmaceutical chemicals.
Article
Results from a process improvement project for preparation of 3-R-quinuclidinol, a highly valuable intermediate for several muscarine-active compounds are described. The studied process was based on the kinetic resolution of racemic 3-quinuclidinol and thus involved a large side-stream production. Our outline for process improvement is based on tha...
Article
Full-text available
Results from a process improvement project for preparation of 3-R-quinuclidinol, a highly valuable intermediate for several muscarine-active compounds are described. The studied process was based on the kinetic resolution of racemic 3-quinuclidinol and thus involved a large side-stream production. Our outline for process improvement is based on tha...
Article
This contribution presents results from a development and optimisation project concerning a synthetic process for iodixanol. Iodixanol is the “active ingredient” in Visipaque (Nycomed Amersham now Amersham Health) a medical X-ray imaging contrast agent. The process step that was developed and optimised comprised a reaction between a tetraacid chlor...
Patent
The present invention provides a process for the production of an organic iodinated X-ray contrast agent, characterized in that process control comprise vibrational (e.r. infrared, Raman or preferably near-infrared) spectroscopic monitoring of the reaction mixture in at least one of the process steps, preferably one of the final reaction steps.
Article
New procedures based on the oxidation by bromine-catalysed hydrogen peroxide in a two-phase system provide simple and cheap transformations of alkylamines to carbonyl derivatives (aldehydes, ketones, carboxylic acid, imides, lactams) through the corresponding acetamides.
Article
A new synthetic process for oxidation of methyl ketones into their corresponding carboxylic acids using a modified alkaline nitrobenzene method is described. By introduction of a more powerful oxidant, such as 1,3-dinitrobenzene, the oxidation reaction proceeds smoothly in aqueous alkaline solution at 100 °C. The procedure can also be used for oxid...
Poster
Full-text available
The need: ln the production of several commercial X-ray contrast agents a substituted acylanilide needs to be N-alkylated in the presence of 1,2-diols. The use of water as solvent for N-alkylations is advantageous from environmental and economical reasons The problem: The nucleophilic centers N/O compete during the alkylation reaction of substrate...
Article
New synthetic procedures for vanillin, iso-vanillin, heliotropin, and protocatechualdehyde starting from catechol are described. The utilisation of statistical experimental design and multivariate modelling and the mechanistic interpretation of the acid and base catalysis in the condensation of catechol derivatives with glyoxylic acid and in the re...
Article
It is shown how the combination of statistical experimental design, multivariate modelling and the interpretation of mechanisms of the involved reactions can be utilised for the development of selective syntheses of industrial interest and low environmental impact. New processes for vanillin, iso-vanillin and heliotropin have been developed from ca...
Article
Tertiary hydroperoxides have been utilized for the electrophilic alkylation of activated aromatic substrates, particularly phenols and phenol ethers. Cumyl (1) and tert-butyl (2) hydroperoxides have shown a greatly different behavior as concerns the catalysis and the regioselectivity. The best catalyst for 1 is TiCl(4), which is completely inactive...
Article
Alkanes are directly iodinated by perfluoroalkyl iodides by a free-radical chain process initiated by t-BuOOH in acetic acid solution. The initially formed iodoalkanes are reduced back to alkanes by excess t-BuOOH; the rate constant for hydrogen abstraction from t-BuOOH by a primary alkyl radical has been roughly evaluated to be 104 M-1 s-1. Two ne...
Article
An optimisation study based upon experimental data obtained from multivariate statistical experimental design and modelling for the haloform reaction used for synthesis of 3,4-dimethoxybenzoic acid from 3,4-dimethoxy acetophenone is reported. It is shown how the different controllable process variables influence both the yield of 3,4-dimethoxybenzo...
Article
The oxidation of lignosulfonates (LS) to vanillin by persulphate, oxygen, and a variety of catalytic systems has been investigated. Cobalt and copper catalysts appeared to be the most effective in the oxidation by oxygen. An investigation where multivariate mathematical and statistical design and modelling have been used for the process optimisatio...
Article
During the production process of the X-ray contrast agent iodixanol the drug substance may be exposed to acid, base, air, heat and daylight, conditions that may cause decomposition products. To investigate the chemical stability of iodixanol under accelerating conditions. Chemometrical stability studies were undertaken to investigate the effect of...
Article
Background: During the production process of the X-ray contrast agent iodixanol the drug substance may be exposed to acid, base, air, heat and daylight, conditions that may cause decomposition products.Objective: To investigate the chemical stability of iodixanol under accelerating conditions.Method: Chemometrical stability studies were undertaken...

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