20 results on '"Hoesl CE"'
Search Results
2. Phase I dose escalation and pharmacokinetic study of BI 2536, a novel Polo-like kinase 1 inhibitor, in patients with advanced solid tumors.
- Author
-
Mross K, Frost A, Steinbild S, Hedbom S, Rentschler J, Kaiser R, Rouyrre N, Trommeshauser D, Hoesl CE, and Munzert G
- Published
- 2008
3. Randomized, double-blind, placebo-controlled dose-finding study of the dipeptidyl peptidase-4 inhibitor linagliptin in pediatric patients with type 2 diabetes.
- Author
-
Tamborlane WV, Laffel LM, Weill J, Gordat M, Neubacher D, Retlich S, Hettema W, Hoesl CE, Kaspers S, and Marquard J
- Subjects
- Adolescent, Age of Onset, Child, Diabetes Mellitus, Type 2 epidemiology, Dipeptidyl-Peptidase IV Inhibitors adverse effects, Dose-Response Relationship, Drug, Double-Blind Method, Female, Humans, Linagliptin adverse effects, Male, Placebos, Diabetes Mellitus, Type 2 drug therapy, Dipeptidyl-Peptidase IV Inhibitors administration & dosage, Linagliptin administration & dosage
- Abstract
Objective: To identify the dose of the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin in pediatric patients with type 2 diabetes (T2D)., Methods: Double-blind, randomized, controlled parallel group study comparing linagliptin 1 and 5 mg once daily, with placebo in 39 patients with T2D aged 10 to below 18 years. The primary efficacy endpoint was the change from baseline in glycated hemoglobin (HbA1c) after 12 weeks of treatment. The key pharmacodynamic endpoint was DPP-4 inhibition during steady-state., Results: Compared to placebo, there was a dose-dependent reduction in mean HbA1c of 0.48% and 0.63% with linagliptin 1 and 5 mg, respectively, associated with corresponding declines in mean fasting plasma glucose (FPG) of 5.6 and 34.2 mg/dL. Median DPP-4 inhibition was 38% with linagliptin 1 mg and 79% with linagliptin 5 mg. Geometric mean trough levels of linagliptin were 3.80 and 7.42 nmol/L in the 1 and 5 mg groups, respectively; levels that were slightly higher than in adult patients with T2D that were most likely caused by higher plasma DPP-4 concentrations in the study population. There were no drug-related adverse events during treatment with either dose of linagliptin., Conclusions: Linagliptin was well tolerated and induced dose-dependent DPP-4 inhibition that was accompanied by corresponding reductions in HbA1c and FPG levels in young people with T2D. The results are consistent with the clinical efficacy and safety profile that have been reported for linagliptin in adult patients with T2D, favoring linagliptin 5 mg over 1 mg., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2018
- Full Text
- View/download PDF
4. Synthesis of platinum(II) chiral tetraamine coordination complexes.
- Author
-
Nefzi A, Hoesl CE, Pinilla C, Kauffman GB, Maggiora GM, Pasquale E, and Houghten RA
- Subjects
- Nitrogen Compounds chemical synthesis, Platinum Compounds chemical synthesis, Solutions chemistry, Stereoisomerism, Combinatorial Chemistry Techniques, Nitrogen Compounds chemistry, Platinum Compounds chemistry
- Abstract
The individual and combinatorial syntheses of individual as well as a mixture-based diversity of 195 112 platinum(II) coordination complexes of chiral tetraamines are described. The use of both solid-phase synthesis and solution phase follow-on approaches were found to best afford the title compounds.
- Published
- 2006
- Full Text
- View/download PDF
5. Affinity of 1-aryl-1,2,3,4-tetrahydroisoquinoline derivatives to the ion channel binding site of the NMDA receptor complex.
- Author
-
Ludwig M, Hoesl CE, Höfner G, and Wanner KT
- Subjects
- Ion Channels chemistry, Ion Channels metabolism, Magnetic Resonance Spectroscopy, Radioligand Assay, Receptors, N-Methyl-D-Aspartate chemistry, Receptors, N-Methyl-D-Aspartate metabolism, Spectrophotometry, Infrared, Tetrahydroisoquinolines metabolism, Ion Channels drug effects, Receptors, N-Methyl-D-Aspartate drug effects, Tetrahydroisoquinolines pharmacology
- Abstract
A series of 1-aryl-1,2,3,4-tetrahydroisoquinoline and 8-methyl-1-aryl-1,2,3,4-tetrahydroisoquinoline derivatives was evaluated for affinity to the PCP binding site of the NMDA receptor complex. The (S)-configured tetrahydroisoquinoline derivative (S)-4 e x HCl bearing a 2-methylphenyl substituent in position 1 of the heterocyclic ring system and a methyl group in position 8 was found to exhibit the highest affinity among the derivatives with a K(i)-value of 0.0374 microM. In addition, this compound shows a remarkable enantioselectivity of binding by being almost 90 times more potent than the corresponding (R)-enantiomer (R)-4 e x HCl. Additionally, a convenient and efficient synthetic approach to racemic 1-aryl-1,2,3,4-tetrahydroisoquinoline derivatives is described.
- Published
- 2006
- Full Text
- View/download PDF
6. New highly potent GABA uptake inhibitors selective for GAT-1 and GAT-3 derived from (R)- and (S)-proline and homologous pyrrolidine-2-alkanoic acids.
- Author
-
Fülep GH, Hoesl CE, Höfner G, and Wanner KT
- Subjects
- Alkanes chemical synthesis, Alkylation, Carboxylic Acids chemical synthesis, Carboxylic Acids chemistry, Carboxylic Acids pharmacology, Methylation, Molecular Structure, Pyrrolidines chemical synthesis, Saponins chemistry, Stereoisomerism, Structure-Activity Relationship, Alkanes chemistry, Alkanes pharmacology, GABA Plasma Membrane Transport Proteins metabolism, GABA Uptake Inhibitors, Proline chemistry, Pyrrolidines chemistry, gamma-Aminobutyric Acid metabolism
- Abstract
We synthesized proline and pyrrolidine-2-alkanoic acid derivatives in their enantiomerically pure form and evaluated them for their affinity to the GABA transport proteins GAT-1 and GAT-3. Among the compounds presented herein, (R)-pyrrolidine-2-acetic acid (R)-4d substituted with a 2-[tris(4-methoxyphenyl)methoxy]ethyl residue at the nitrogen atom showed the highest affinity at GAT-3 (IC(50) = 3.1 microM) comparable with the well-known GAT-3 blocker (S)-SNAP-5114. Compound (R)-4d displayed excellent subtype selectivity for GAT-3 (GAT-3:GAT-1 = 20:1). (S)-2-pyrrolidineacetic acid derivatives (S)-4b provided with a 4,4-diphenylbut-3-en-1-yl moiety and (S)-4c substituted with a 4,4-[di(3-methylthiophen-2-yl)]phenylbut-3-en-1-yl residue at the nitrogen atom exhibited IC(50) values of 0.396 microM and 0.343 microM at the GAT-1 protein, respectively.
- Published
- 2006
- Full Text
- View/download PDF
7. [Antiandrogen therapy of prostate carcinoma].
- Author
-
Altwein J and Hoesl CE
- Subjects
- Humans, Male, Neoplasm Recurrence, Local diagnosis, Neoplasm Recurrence, Local drug therapy, Neoplasm Recurrence, Local pathology, Neoplasm Staging, Prognosis, Prostate drug effects, Prostate pathology, Prostatic Neoplasms diagnosis, Prostatic Neoplasms pathology, Androgen Antagonists therapeutic use, Orchiectomy, Prostatic Neoplasms drug therapy, Testosterone antagonists & inhibitors
- Abstract
Thanks to improved examination techniques, many cases of prostate cancer are now being diagnosed in younger patients. It is therefore of ever greater importance that treatment should have no great impact on the patient's quality of life. Nonsteroidal antiandrogens have a more favorable side effect profile than surgical or pharmacological castration, since the serum concentration of testosterone remains within the normal range. Depending on the stage of the illness, they can be employed in the form of monotherapy as an adjuvant to prostatectomy or radiotherapy in local advanced prostate cancer, and as components of maximum androgens blockade.
- Published
- 2006
- Full Text
- View/download PDF
8. Alpha-adrenoceptors are a common denominator in the pathophysiology of erectile function and BPH/LUTS--implications for clinical practice.
- Author
-
Yassin A, Saad F, Hoesl CE, Traish AM, Hammadeh M, and Shabsigh R
- Subjects
- Adrenergic alpha-Antagonists therapeutic use, Aging physiology, Drug Therapy, Combination, Erectile Dysfunction drug therapy, Erectile Dysfunction epidemiology, Humans, Male, Muscle, Smooth, Vascular chemistry, Penile Erection physiology, Phosphodiesterase Inhibitors therapeutic use, Prostatic Hyperplasia drug therapy, Receptors, Adrenergic, alpha analysis, Risk Factors, Sexual Dysfunction, Physiological drug therapy, Sexual Dysfunction, Physiological physiopathology, Urologic Diseases drug therapy, Erectile Dysfunction physiopathology, Prostatic Hyperplasia physiopathology, Receptors, Adrenergic, alpha physiology, Urologic Diseases physiopathology
- Abstract
A literature search of PubMed documented publications and abstracts from proceedings of scientific meetings was made to review the available data on benign prostatic hyperplasia/lower urinary tract symptoms (BPH/LUTS) and erectile dysfunction (ED) with a special focus on the role of alpha-adrenoceptors as critical mediators of pathophysiology. The reader is introduced to clinical results on the therapeutic potential of alpha-blockers alone and in combination with phosphodiesterase type 5 (PDE-5) inhibitors in the treatment of ED associated with LUTS/BPH. Epidemiological studies clearly show that an association exists between ED and LUTS/BPH. The severity of LUTS is correlated with the risk for ED. A significant number of LUTS/BPH patients are nonresponsive to the common ED treatment with PDE-5 inhibitors. As smooth muscle contractility is regulated by adrenoceptors in the corpus cavernosum, prostate and detrusor, the alpha-adrenoceptor system may be considered a common pathophysiological mediator in the development of ED and LUTS/BPH. Blockade of alpha-adrenoceptors for the treatment of BPH/LUTS may have the potential of improving sexual function. Conversely, PDE-5 inhibitors may exhibit positive effects in LUTS patients. Pilot studies on combination regimens of alpha-adrenoceptor antagonists and PDE-5 inhibitors have yielded encouraging results in LUTS patients with persistent ED. On the basis of pharmacological and clinical evidence, it is established that the alpha-adrenoceptor system plays an important role in the pathophysiology of ED and LUTS secondary to BPH. Larger trials on the combination of alpha-adrenoceptor antagonists with PDE-5 inhibitors are necessary to develop an integrated treatment approach for BPH/LUTS patients with comorbid ED.
- Published
- 2006
- Full Text
- View/download PDF
9. Biphosphonates in advanced prostate and renal cell cancer--current status and potential applications.
- Author
-
Hoesl CE and Altwein JE
- Subjects
- Bone Neoplasms drug therapy, Bone Neoplasms secondary, Disease Progression, Humans, Kidney Neoplasms pathology, Male, Prostatic Neoplasms pathology, Kidney Neoplasms drug therapy, Organophosphonates therapeutic use, Prostatic Neoplasms drug therapy
- Abstract
Objective: This review summarizes recent findings on the therapeutic benefits of biphosphonates in patients with advanced prostate or renal cell carcinoma (RCC). The role of biphosphonates in ADT-induced osteoporosis and delay of skeletal-related events (SREs) in metastatic bone disease is discussed. A brief overview on the proposed modes of action is given., Methods: Literature search of PubMed documented publications and abstracts from meetings., Results: Among the biphosphonates currently available, zoledronic acid is the only one known to be capable of delaying SREs in RCC and prostate cancer patients. Zoledronic acid counteracts cancer treatment-induced osteoporosis in men with prostate malignancies. The antitumor activity of biphosphonates found in vitro and in vivo is intriguing and has to be further assessed in clinical studies., Conclusion: Due to its unique properties, zoledronic acid is a breakthrough in the management of metastatic bone disease in patients with advanced prostate cancer and RCC. It significantly improves the patients' quality of life, drastically prolongs time to first SRE, and showed a positive but not significant effect on survival.
- Published
- 2006
- Full Text
- View/download PDF
10. Solid phase synthesis of 3,4,7-trisubstituted 4,5,8,9-tetrahydro-3H-imidazo[1,2-a][1,3,5]triazepin-2(7H)-thiones and N-alkyl-4,5,7,8-tetrahydro-3H-imidazo[1,2-a][1,3,5]triazepin-2-amines.
- Author
-
Hoesl CE, Ostresh JM, Houghten RA, and Nefzi A
- Subjects
- Chromatography, High Pressure Liquid, Cyclization, Molecular Structure, Triazines chemistry, Combinatorial Chemistry Techniques methods, Guanidines chemistry, Triazines chemical synthesis
- Abstract
The solid-phase parallel synthesis of 3,4,7-trisubstituted 4,5,8,9-tetrahydro-3H-imidazo[1,2-a][1,3,5]triazepin-2(7H)-thiones and N-alkyl-4,5,7,8-tetrahydro-3H-imidazo[1,2-a][1,3,5]triazepin-2-amines starting from resin-bound dipeptides is described. The key synthetic steps involve the cylization of an amino and a guanidino functionality using thiocarbonyldiimidazole and the subsequent transformation of the resulting thiourea moiety to a substituted guanidine group using HgCl(2) and various amines. Following cleavage from the resin, the desired products were obtained in good yields and good to moderate purities, depending on the building blocks employed.
- Published
- 2006
- Full Text
- View/download PDF
11. Reversible, non-barrier male contraception: status and prospects.
- Author
-
Hoesl CE, Saad F, Pöppel M, and Altwein JE
- Subjects
- Animals, Clinical Trials as Topic, Contraception, Barrier, Female, Humans, Male, Patient Acceptance of Health Care, Pregnancy, PubMed, Testosterone metabolism, Testosterone therapeutic use, Contraceptive Agents, Contraceptive Agents, Male
- Abstract
Objective: Male, non-barrier, contraceptive options are limited to vasectomy and inadequate methods such as withdrawal and periodic abstinence. Herein we give an overview of current research on male contraception by pharmacological means., Methods: Literature search of PubMed documented publications and abstracts from meetings., Results: Cross-cultural surveys show men's willingness to carry contraceptive responsibility. Clinical trials substantiate that hormonal contraception involving suppression of gonadotropins holds the best promise to provide a male pharmacological contraceptive. Androgens have been demonstrated to induce reversible infertility particularly in combination with certain progestins and GnRH antagonists. Advances in non-endocrine contraception include intervention with triptolide derivatives, alkylated imino sugars, and immunization by eppin., Conclusion: The prospect of a pharmacological, male contraceptive has been considerably advanced in recent years. Long-term studies involving a greater number of subjects may result in a safe, reversible and effective means. Asia is likely to be the first market for male, hormonal contraceptive methods. The clinical evaluation of non-endocrine approaches may ultimately lead to an alternative to hormone-based male contraception.
- Published
- 2005
- Full Text
- View/download PDF
12. Dehydroepiandrosterone treatment in the aging male--what should the urologist know?
- Author
-
Saad F, Hoesl CE, Oettel M, Fauteck JD, and Römmler A
- Subjects
- Cardiovascular Physiological Phenomena drug effects, Clinical Trials as Topic, Dietary Supplements, Hormone Replacement Therapy, Humans, Male, Penile Erection drug effects, Aging drug effects, Aging physiology, Dehydroepiandrosterone administration & dosage, Dehydroepiandrosterone pharmacology
- Abstract
Objective: Dehydroepiandrosterone (DHEA) has attracted considerable attention as a means against the decrements of aging. This review will summarize clinical studies evaluating DHEA as a treatment option for age-related conditions and diseases., Methods: Literature search of PubMed documented publications and abstracts from meetings., Results: The collected data indicate that DHEA supplementation to counteract its gradual decrease over age is beneficiary. Positive effects on the cardiovascular system, body composition, BMD, the skin, the CNS, and the immune system have been reported. Improvement of sexual function by DHEA has been demonstrated., Conclusion: Although long-term clinical trials (applying the standards of evidence-based methods) are not available at present, the consistency of the data and the extensive practical experience may justify the use of DHEA in aging men given the rules of classical endocrinology are thoroughly followed including diagnosis based on clinical picture and biochemical evidence, compliance to periodic evaluations, and individual dose adjustment to maintain serum concentrations in the physiological range of young males. Being one among other important hormonal factors, DHEA can delay and correct age-related disorders only to a certain degree.
- Published
- 2005
- Full Text
- View/download PDF
13. NMDA-NR2B subtype selectivity of stereoisomeric 2-(1,2,3,4-tetrahydro-1-isoquinolyl)ethanol derivatives.
- Author
-
Höfner G, Hoesl CE, Parsons C, Quack G, and Wanner KT
- Subjects
- Binding Sites, Dizocilpine Maleate pharmacokinetics, Ethanol chemical synthesis, Kinetics, Models, Molecular, Molecular Structure, Potassium Channels physiology, Stereoisomerism, Ethanol analogs & derivatives, Ethanol pharmacology, Excitatory Amino Acid Antagonists pharmacology, Isoquinolines chemical synthesis, Isoquinolines pharmacology, Receptors, N-Methyl-D-Aspartate antagonists & inhibitors
- Abstract
Enantiopure 2-(1,2,3,4-tetrahydro-1-isoquinolyl)ethanol derivatives were tested for their affinity to the ifenprodil binding site of the NMDA receptor, their potency to inhibit [3H]MK801 binding and their NMDA-NR2B subtype selectivity. The (1S,1'S)-configurated series displayed the highest affinity to the ifenprodil binding site. A reasonable potency and NMDA-NR2B subtype selectivity was found for (1S,1'S)-4c (R1=Me, R2=OMe). A high affinity to HERG K+ channels, however, suggests that (1S,1'S)-4c may involve an increased risk of cardiovascular side effects.
- Published
- 2005
- Full Text
- View/download PDF
14. [Early detection of cancer of the prostate. Pros and cons].
- Author
-
Hoesl CE and Altwein JE
- Subjects
- Aged, Follow-Up Studies, Germany epidemiology, Humans, Male, Middle Aged, Multicenter Studies as Topic, Physical Examination, Practice Guidelines as Topic, Prostatectomy, Prostatic Neoplasms blood, Prostatic Neoplasms epidemiology, Prostatic Neoplasms mortality, Prostatic Neoplasms surgery, Randomized Controlled Trials as Topic, Risk, Sensitivity and Specificity, Time Factors, Mass Screening psychology, Prostate-Specific Antigen blood, Prostatic Neoplasms diagnosis, Prostatic Neoplasms prevention & control
- Abstract
Since the introduction of PSA determination for the detection of cancer of the prostate, there have been discussions of the pros and cons of PSA screening for early detection of this cancer. The PSA test used in combination with digital rectal examination has proven to be a superior diagnostic instrument for the diagnosis of malignant prostate disease at an early stage. The German Guideline Catalog for the early detection of carcinoma of the prostate recommends measurement of the PSA from the age of 45 onwards in patients who have first been comprehensively informed about the further proceedings in the event of a positive result. To date, PSA screening has not been shown to lower the disease-specific mortality rate. Two ongoing randomized, multicentre studies (ERSPC and PLCO) are expected to throw more light on the matter.
- Published
- 2005
15. Erectile dysfunction (ED) is prevalent, bothersome and underdiagnosed in patients consulting urologists for benign prostatic syndrome (BPS).
- Author
-
Hoesl CE, Woll EM, Burkart M, and Altwein JE
- Subjects
- Erectile Dysfunction diagnosis, Humans, Male, Middle Aged, Prevalence, Quality of Life, Risk Factors, Surveys and Questionnaires, Erectile Dysfunction complications, Erectile Dysfunction epidemiology, Prostatic Hyperplasia complications
- Abstract
Objectives: The aim of the present study was to determine the prevalence of erectile dysfunction (ED) in patients visiting office-based urologists in Germany because of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH), and to evaluate the impact of ED on quality of life (QoL) in these patients., Methods: 500 office-based urologists in Germany were invited to evaluate 20 consecutive patients for erectile dysfunction, who presented because of BPH-related LUTS. Physicians provided information on demographic factors, duration and treatment history of BPH, severity of LUTS, ED risk factors, and assessed the patient for the clinical diagnosis of ED. Patients were asked to complete the German version of the IPSS to measure LUTS severity. ED-patients quantified erectile dysfunction and impact on quality of life with validated German questionnaires (Cologne assessment of male erectile dysfunction KEED, and Qol-Med)., Results: Office-based urologists were aware of ED in 37.3% of 8768 patients presenting for LUTS before the study, 14.7% of patients were treated for ED. After the study-related assessment, physicians diagnosed ED in 62.1% of these patients and planned treatment in 46.9%. Severity of LUTS and ED prevalence correlated significantly after age-stratification. The incidence of ED was increased in patients with established ED risk factors. Mean QoL-Med score (best QoL: 100, worst QoL: 0) was 53.8 in patients with ED and 50.1 in ED-patients considering treatment., Conclusion: ED is highly prevalent in LUTS patients visiting an office-based urologist and is accompanied by a profound impact on the quality of life. Apparently, even during an urological consultation many ED-patients are hesitant to actively ask for treatment. Sexual issues should become key considerations for physicians managing patients with LUTS, especially since effective and well established oral treatment for ED is available.
- Published
- 2005
- Full Text
- View/download PDF
16. The probiotic approach: an alternative treatment option in urology.
- Author
-
Hoesl CE and Altwein JE
- Subjects
- Animals, Calcium Oxalate chemistry, Humans, Kidney Calculi diet therapy, Treatment Outcome, Complementary Therapies methods, Probiotics therapeutic use, Urologic Diseases diet therapy, Urology methods
- Abstract
Objective: The prophylactic and therapeutic use of probiotic microorganisms is a wide and still controversial field. The review paper is aimed to summarize recent findings on the health-benefiting effects of probiotics in urological diseases. The use of certain beneficial strains against urogenital infections, bladder cancer recurrence and renal stone formation is discussed., Methods: Literature search of PubMed documented publications and abstracts from meetings., Results: Various clinical trials have now been performed which substantiate the beneficial effects of the probiotic strains L. rhamnosus GR-1, L. fermentum RC-14 and L. crispatus CTV-05 against urogenital infections, such as urinary tract infections and bacterial vaginosis. The potential of L. casei Shirota to reduce the recurrence rate of bladder cancer is one of the most intriguing examples for the use of probiotics in medical practice. The use of O. formigenes in the prevention of calcium oxalate stone disease was only recently suggested and needs to be further investigated., Conclusion: Clinical trials increasingly provide a profound scientific basis for the use of probiotics in medicinal practice including urology. Efforts to make probiotic products available which are validated according to the guidelines recommended by the WHO and FAO and produced according to Good Manufacturing Practice will contribute to the acceptance of probiotic therapy by both the physicians and the patients.
- Published
- 2005
- Full Text
- View/download PDF
17. Synthesis and biological evaluation of new GABA-uptake inhibitors derived from proline and from pyrrolidine-2-acetic acid.
- Author
-
Zhao X, Hoesl CE, Hoefner GC, and Wanner KT
- Subjects
- Animals, Biological Transport, Brain drug effects, Brain metabolism, Cattle, GABA Plasma Membrane Transport Proteins, Molecular Structure, Structure-Activity Relationship, Swine, gamma-Aminobutyric Acid metabolism, GABA Antagonists chemical synthesis, GABA Antagonists pharmacology, Membrane Transport Modulators, Membrane Transport Proteins antagonists & inhibitors, Proline analogs & derivatives, Proline chemistry
- Abstract
Several synthetic approaches to N-alkylated derivatives of 4-hydroxypyrrolidine-2-carboxylic acid and 4-hydroxypyrrolidine-2-acetic acid are described. The final compounds have been evaluated as potential inhibitors of the GABA transport proteins GAT-1 and GAT-3. The biological assays used were based on bovine material or porcine brain. As compared to the corresponding 4-unsubstituted compounds, the 4-hydroxypyrrolidine-2-carboxylic acid and 4-hydroxypyrrolidine-2-acetic acid derivatives showed a significant decrease in the inhibitory potency at both GAT-1 and GAT-3 with only four compounds having reasonable affinity to GAT-1 (IC(50): 5.1, 6.6 and 9.4 microM) or GAT-3 (IC(50): 19.9 microM), respectively. The biological data of the 4-hydroxypyrrolidine-2-acetic acid derivatives indicates that (2S)-configuration at the C-2 position for potent inhibition of GAT-1 and (4R)-configuration at the C-4 position for potent inhibition of GAT-3 may be crucial.
- Published
- 2005
- Full Text
- View/download PDF
18. Halogenoalkyl isocyanates as bifunctional reagents in an Aza-Wittig/heterocyclization reaction on the solid phase: efficient entry into new tetracyclic benzimidazole systems.
- Author
-
Hoesl CE, Nefzi A, and Houghten RA
- Subjects
- Alkylation, Crystallography, X-Ray, Cyclization, Magnetic Resonance Spectroscopy, Models, Chemical, Molecular Structure, Resins, Synthetic, Stereoisomerism, Benzimidazoles chemical synthesis, Halogens chemistry, Isocyanates chemistry, Polycyclic Compounds chemistry
- Abstract
An efficient one-pot procedure for the solid-phase synthesis of new tetracyclic 1,3,5-triazino[1,2-a]benzimidazolium derivatives starting from resin-bound benzimidazoles is described. The synthetic strategy involves an unprecedented one-pot Aza-Wittig/heterocyclization/substitution reaction sequence using halogenoalkyl isocyanates. The structure of the tetracyclic ring system was determined by two-dimensional NMR experiments and X-ray analysis.
- Published
- 2004
- Full Text
- View/download PDF
19. Parallel solid-phase synthesis of 2-imino-4-oxo-1,3,5-triazino[1,2-a]benzimidazoles via tandem aza-Wittig/heterocumulene-mediated annulation reaction.
- Author
-
Hoesl CE, Nefzi A, and Houghten RA
- Subjects
- Catalysis, Chromatography, High Pressure Liquid, Indicators and Reagents, Magnetic Resonance Spectroscopy, Polycyclic Compounds chemistry, Polypropylenes chemistry, Resins, Synthetic, Benzimidazoles chemical synthesis, Triazines chemical synthesis
- Abstract
The parallel synthesis of a large number of 2-imino-4-oxo-1,3,5-triazino[1,2-a]benzimidazole derivatives via a solid-phase 1,3,5-triazino-annulation reaction is described. The solid-phase approach involves the in situ generation of iminophosphorane derivatives derived from resin-bound 2-aminobenzimidazoles employing Mitsunobu conditions. The subsequent Aza-Wittig reaction of the iminophosphoranes with isocyanates leads to highly reactive carbodiimides, which undergo an intramolecular heterocyclization reaction to form tetrasubstituted 2-imino-4-oxo-1,3,5-triazino[1,2-a]benzimidazoles in high yields (74-94%) and good purity (>80%).
- Published
- 2003
- Full Text
- View/download PDF
20. Mixture-based combinatorial libraries: from peptides and peptidomimetics to small molecule acyclic and heterocyclic compounds.
- Author
-
Hoesl CE, Nefzi A, Ostresh JM, Yu Y, and Houghten RA
- Subjects
- Combinatorial Chemistry Techniques methods, Heterocyclic Compounds chemical synthesis, Peptide Library, Peptides chemical synthesis
- Published
- 2003
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.