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1.
Clin Exp Immunol ; 215(3): 302-312, 2024 02 19.
Article in English | MEDLINE | ID: mdl-38190323

ABSTRACT

Inter-α-trypsin inhibitor heavy chain 4 (ITIH4) is a major protein in serum and reported to be upregulated at the onset of rheumatoid arthritis (RA). Its citrullinated form, cit-ITIH4, is specifically found in the serum and synovial fluid of patients with RA. However, the detailed function of ITIH4 in arthritis remains unknown. The aim of this study was to clarify the role of ITIH4 and cit-ITIH4 using experimental arthritis models. ITIH4 and cit-ITIH4 expression was examined in steady-state mice and two different arthritis models, and their pathological effects were examined in Itih4-deficient mice. In naïve C57BL/6 (WT) mice, ITIH4 was expressed as mRNA in the liver and the lung and was expressed as protein in serum and hepatocytes. In K/BxN serum transferred arthritis (K/BxN-STA) and collagen-induced arthritis (CIA), ITIH4 and cit-ITIH4 in sera were increased before the onset of arthritis, and cit-ITIH4 was further increased at the peak of arthritis. In Itih4-deficient mice, citrullinated proteins in serum and joints, especially 120 kDa protein, were clearly diminished; however, there was no significant difference in arthritis severity between WT and itih-/- mice either in the K/BxN-STA or CIA model. CIA mice also exhibited pulmonary lesions and itih4-/- mice tended to show enhanced inflammatory cell aggregation compared to WT mice. Neutrophils in the lungs of itih4-/- mice were significantly increased compared to WT mice. In summary, ITIH4 itself did not alter the severity of arthritis but may inhibit autoimmune inflammation via suppression of neutrophil recruitment.


Subject(s)
Alpha-Globulins , Arthritis, Experimental , Arthritis, Rheumatoid , Animals , Humans , Mice , Disease Models, Animal , Mice, Inbred C57BL , Proteins
2.
Rheumatol Int ; 44(3): 549-556, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38170205

ABSTRACT

IgG4-related disease (IgG4-RD) is a systemic condition in which IgG4+ plasma cell infiltration and fibrosis cause organ swelling and lead to diverse clinical manifestations. Although IgG4-RD typically responds to glucocorticoids (GCs), relapse during tapering occurs and an early GC-sparing approach might therefore be beneficial. Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with multiple symptoms that is also treated with GCs as a first-line therapy. Recently, belimumab, a recombinant human IgG-1λ monoclonal antibody that inhibits B-cell activating factor, was approved, but reports of use for IgG4-RD are scarce. Here, we present a rare case of IgG4-RD complicated with SLE which was successfully treated with belimumab. A 67-year-old man was diagnosed with IgG4-RD based on a high serum IgG4 level and histopathological findings. Furthermore, he had pericardial effusion on echocardiography, and laboratory tests revealed thrombocytopenia, autoimmune hemolysis, positive anti-nuclear antibodies, positive anti-DNA antibodies, and hypocomplementemia. These data led to an SLE diagnosis. Treatment was started with prednisolone at 40 mg/day, plus hydroxychloroquine, which initially improved both the SLE and IgG4-RD symptoms. During the GC tapering, belimumab was added and clinical symptoms resolved completely. Our case and the literature review summarize reported rare overlapping cases of IgG4-RD and SLE and suggest that belimumab is a promising candidate for the treatment of IgG4-RD.


Subject(s)
Immunoglobulin G4-Related Disease , Lupus Erythematosus, Systemic , Male , Humans , Aged , Immunoglobulin G4-Related Disease/complications , Immunoglobulin G4-Related Disease/diagnosis , Immunoglobulin G4-Related Disease/drug therapy , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/diagnosis , Lupus Erythematosus, Systemic/drug therapy , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal/therapeutic use , Glucocorticoids/therapeutic use , Immunoglobulin G , Immunosuppressive Agents/therapeutic use , Treatment Outcome
3.
Intern Med ; 63(5): 743-747, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37468247

ABSTRACT

We present the case of a 17-year-old woman with IgA vasculitis (IgAV) who presented with relapsing gastrointestinal (GI) symptoms that were refractory to glucocorticoid and combination therapy with cyclosporine A, azathioprine or mycophenolate mofetil (MMF). The patient responded well to remission induction with intravenous cyclophosphamide (IVCY) and was successfully maintained with MMF. Remission induction with IVCY followed by maintenance therapy with MMF was effective in a patient with multidrug-resistant IgAV with GI lesions.


Subject(s)
IgA Vasculitis , Lupus Nephritis , Female , Humans , Adolescent , Mycophenolic Acid/therapeutic use , Immunosuppressive Agents/therapeutic use , Cyclophosphamide/therapeutic use , Azathioprine , Remission Induction
4.
Sci Rep ; 12(1): 21334, 2022 12 09.
Article in English | MEDLINE | ID: mdl-36494453

ABSTRACT

Recent studies have suggested that the clinical features of elderly-onset adult-onset Still's disease (AOSD) differ from those of young and middle-aged-onset patients, whereas the details remain unclear, and cytokine profiles of elderly-onset AOSD have not been reported. To clarify the clinical features and cytokine profiles of elderly-onset AOSD, we examined patients with AOSD who developed the disease between January 2006 and September 2021. We divided the patients into the young and middle-aged-onset group (aged < 65 years) and the elderly-onset group (aged ≥ 65 years) and compared the groups in terms of patient characteristics, clinical symptoms, laboratory findings including serum interleukin (IL)-6 and IL-18, treatment, and prognosis. A total of 48 patients were examined (10 in the elderly-onset group). In the elderly-onset group, atypical rash was significantly more frequent, typical rash and splenomegaly were significantly less frequent, white blood cell count and neutrophil ratio were significantly higher and serum IL-6 levels were significantly lower. Serum IL-6 showed a significantly negative correlation with age at onset. Treatment and relapse were comparable between the 2 groups, whereas infections were significantly more frequent in the elderly-onset group. The clinical features and cytokine profiles of elderly-onset AOSD might differ from those of young and middle-aged-onset AOSD.


Subject(s)
Exanthema , Still's Disease, Adult-Onset , Adult , Middle Aged , Aged , Humans , Interleukin-6 , Enzyme-Linked Immunosorbent Assay
5.
Intern Med ; 61(17): 2671-2675, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35135914

ABSTRACT

Pleural effusion is a rare manifestation in synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome, which is characterized by the presence of osteoarticular lesions and dermatological involvement. We herein report a 71-year-old man with pleural effusion resulting from SAPHO syndrome. He was successfully treated using corticosteroids and has experienced no recurrence for one year. We should consider SAPHO syndrome when encountering cases of anterior chest pain and pleural fluid.


Subject(s)
Acne Vulgaris , Acquired Hyperostosis Syndrome , Hyperostosis , Osteitis , Pleural Effusion , Synovitis , Acne Vulgaris/pathology , Acquired Hyperostosis Syndrome/complications , Acquired Hyperostosis Syndrome/diagnosis , Acquired Hyperostosis Syndrome/drug therapy , Aged , Humans , Hyperostosis/pathology , Male , Osteitis/pathology , Pleural Effusion/diagnostic imaging , Pleural Effusion/etiology , Synovitis/diagnosis , Synovitis/diagnostic imaging
6.
Intern Med ; 60(18): 2887-2897, 2021.
Article in English | MEDLINE | ID: mdl-34526442

ABSTRACT

Objective To identify factors associated with pneumomediastinum during management of connective tissue disease (CTD)-related interstitial lung disease (ILD). Methods Patients diagnosed with pneumomediastinum after the initiation of corticosteroid therapy for their CTD-ILD were enrolled. The baseline characteristics of patients who developed pneumomediastinum after the initiation of corticosteroid therapy (n=13, all occurring within 120 days) were compared to those of patients who did not develop pneumomediastinum (n=49). A multivariate logistic regression analysis was performed to identify factors associated with pneumomediastinum. A receiver operating characteristic (ROC) curve analysis was also performed to assess the predictive performance. Results The body mass index (BMI) [odds ratio (OR) (95% confidence interval (CI)) 0.482 (0.272-0.853)] and serum lactate dehydrogenase (LDH) [OR (95% CI) 1.013 (1-1.025)] levels at baseline were identified as independent factors associated with pneumomediastinum after corticosteroid initiation. The optimal cut-off points of the BMI and LDH levels for predicting pneumomediastinum development, as estimated by the Youden index, were 20.2 kg/m2 and 378 U/L, respectively. LDH showed a sensitivity of 61.5% and the highest specificity of 87.8%. Importantly, combining these markers resulted in the highest sensitivity of 100% and a specificity of 71.4%. Conclusion A low BMI and high serum LDH levels at baseline are useful predictive factors for pneumomediastinum development in CTD-ILD patients.


Subject(s)
Connective Tissue Diseases , Lung Diseases, Interstitial , Mediastinal Emphysema , Biomarkers , Connective Tissue Diseases/complications , Humans , Lung Diseases, Interstitial/diagnosis , Lung Diseases, Interstitial/epidemiology , Mediastinal Emphysema/diagnostic imaging , Mediastinal Emphysema/etiology , Prognosis , Retrospective Studies
7.
Int J Mol Sci ; 22(14)2021 Jul 16.
Article in English | MEDLINE | ID: mdl-34299252

ABSTRACT

Neutrophils and their extracellular traps have been shown to play an important role in the pathogenesis of rheumatoid arthritis (RA), but the detailed mechanisms in joints are still unclear, and their regulation remains to be solved. Here, we explored neutrophil extracellular trap (NET)osis in experimental models of arthritis and further investigated the effects of interleukin-6 (IL-6) inhibition in neutrophils and NETosis. In skins of peptide GPI-induced arthritis (pGIA), citrullinated protein was detected as well as citrullinated histone expression in immunized skin but this was not specific to pGIA. Citrullinated histone expression in pGIA joints was specific to pGIA and was merged with neutrophil elastase, suggesting NETosis. Neutrophils in joints tend to upregulate IL-6 receptors when compared with bone marrow neutrophils. Administration of mouse anti-IL-6 receptor antibodies in pGIA suppressed arthritis in association with a decrease in neutrophil infiltration and NETosis in joints. In the plasma of RA patients, citrullinated protein was significantly reduced after tocilizumab treatment. Our results suggest that IL-6 enhances neutrophil chemotaxis and NETosis in inflammatory joints and could be the source of citrullinated proteins.


Subject(s)
Arthritis, Rheumatoid/immunology , Extracellular Traps/metabolism , Interleukin-6/metabolism , Animals , Arthritis, Rheumatoid/metabolism , Autoantibodies/immunology , Autoimmune Diseases/immunology , Autoimmune Diseases/metabolism , Citrulline/metabolism , Extracellular Traps/genetics , Extracellular Traps/physiology , Histones/metabolism , Interleukin-6/immunology , Joints/immunology , Leukocyte Elastase/metabolism , Male , Mice , Mice, Inbred DBA , Neutrophils/metabolism , Receptors, Interleukin-6/metabolism
8.
Gastric Cancer ; 24(4): 946-958, 2021 07.
Article in English | MEDLINE | ID: mdl-33743112

ABSTRACT

BACKGROUND: ATTRACTION-2 demonstrated that nivolumab improved overall survival (OS) vs placebo in patients with advanced gastric cancer treated with ≥ 2 chemotherapy regimens. However, its long-term efficacy and outcome of treatment beyond progression (TBP) with nivolumab have not been clarified. METHODS: The 3-year follow-up data were collected. A subset analysis was performed to explore the efficacy of TBP by assessing postprogression survival (PPS) after the first event of disease progression. RESULTS: Overall, 493 patients were randomized (2:1) to receive nivolumab (n = 330) or placebo (n = 163). With a median follow-up of 38.5 (range 36.1-47.5) months, OS of the nivolumab group was significantly longer compared to the placebo group (median 5.3 vs 4.1 months; 3-year survival rate, 5.6% vs 1.9%; hazard ratio [HR], 0.62 [95% confidence interval (CI) 0.50-0.75], P < 0.0001). The median OS of responders (n = 32) who achieved complete response or partial response was 26.7 months and the 3-year survival rate was 35.5% in the nivolumab group. Overall, 109 patients in the nivolumab group and 37 patients in the placebo group received TBP. PPS tended to be longer in the nivolumab group vs placebo group (median 5.8 vs 4.5 months; HR [95% CI], 0.69 [0.47-1.01], P = 0.057). In contrast, PPS was similar between both treatment groups in non-TBP patients (median 2.3 vs 2.2 months; HR 0.90, P = 0.42). CONCLUSIONS: Long-term efficacy of nivolumab was confirmed at the 3-year follow-up, and a survival benefit of TBP with nivolumab was suggested. Biomarkers for selecting patients suitable for TBP with nivolumab should be identified in the future.


Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Nivolumab/therapeutic use , Stomach Neoplasms/drug therapy , Adult , Aged , Disease Progression , Double-Blind Method , Female , Follow-Up Studies , Humans , Male , Middle Aged , Progression-Free Survival , Stomach Neoplasms/mortality , Survival Rate , Treatment Outcome
10.
Mod Rheumatol ; 31(6): 1107-1112, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33496215

ABSTRACT

OBJECTIVES: The primary objective is to reveal the effect of hydroxychloroquine (HCQ) treatment on corrected QT (QTc) interval in patients with systemic lupus erythematosus (SLE). The secondary objective is to investigate factors that affect QTc prolongation. METHODS: SLE patients who had electrocardiograms between 2015 and 2020 were recruited and assigned to two groups based on whether they were treated with HCQ (HCQ group) or not (control group). Change of QTc before and after HCQ administration in the HCQ group was measured and compared with the control group. Patients treated with HCQ were further divided into two groups based on presence or absence of QTc prolongation and the characteristics were compared. RESULTS: In total, 126 patients were recruited, of whom 42 were treated with HCQ. In the HCQ group, the mean QTc significantly increased (p < .001), while there was no significant difference of mean QTc in the control group. Moreover, those in the HCQ group with QTc prolongation showed a significantly higher proportion of hypertension and longer SLE duration compared to those without QTc prolongation. However, the multiple logistic regression analysis showed that there were no significant differences among them. CONCLUSION: HCQ could induce QTc prolongation in SLE patients. It might be better that the possibility of QTc prolongation was taken into consideration when HCQ was administered in the patients with longer disease duration of SLE and coincidence of hypertension.


Subject(s)
Antirheumatic Agents , Long QT Syndrome , Lupus Erythematosus, Systemic , Antirheumatic Agents/adverse effects , Electrocardiography , Humans , Hydroxychloroquine/adverse effects , Long QT Syndrome/chemically induced , Long QT Syndrome/diagnosis , Long QT Syndrome/drug therapy , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/drug therapy
11.
Mod Rheumatol ; 31(6): 1129-1134, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33480825

ABSTRACT

OBJECTIVES: We compared large vessel vasculitis (LVV) clinical features between age groups. METHODS: We retrospectively examined clinical features and therapies in 41 LVV patients at our hospital from January 2010 to March 2020. We compared two patient groups, elderly (≥50 years) and young (<50 years). RESULTS: Of all patients, 29 were elderly and 12 were young. In the younger group, upper extremity symptoms (p <.05), bruits (p <.01), and cardiovascular complications (p <.01) were more common. Of the elderly group, 7 (24%) met classification criteria for giant cell arteritis while none of the younger group met these criteria; however, 10 (83%) of the younger group and 3 (10%) of the elderly group met the ACR classification criteria for Takayasu arteritis (p <.01). In the elderly group, 16 patients (66%) met no criteria (p <.01). There were no significant differences in laboratory findings but imaging showed a significantly higher incidence of head and neck artery lesions in the younger group (p <.05). The younger group was more likely to receive additional tocilizumab (p <.01) and cardiovascular complications were more likely to occur in younger patients (p < .01). CONCLUSION: LVV clinical features differed between elderly- and young-age-onset groups.


Subject(s)
Age Factors , Age of Onset , Giant Cell Arteritis , Takayasu Arteritis , Aged , Aged, 80 and over , Female , Giant Cell Arteritis/complications , Giant Cell Arteritis/diagnosis , Giant Cell Arteritis/drug therapy , Humans , Male , Middle Aged , Retrospective Studies , Takayasu Arteritis/diagnosis , Takayasu Arteritis/diagnostic imaging , Young Adult
12.
Mod Rheumatol ; 31(3): 636-642, 2021 May.
Article in English | MEDLINE | ID: mdl-32930047

ABSTRACT

OBJECTIVES: To investigate the clinical features and prognosis of nocardiosis complicated by connective tissue diseases (CTDs). METHODS: We examined patients with CTDs who were diagnosed with nocardiosis from October 2004 to 2019. We retrospectively investigated patient characteristics and therapeutic outcomes. We then performed a comparison between survivors and non-survivors. RESULTS: Fourteen patients were examined. Underlying CTDs were systemic lupus erythematosus (28.6%), vasculitis syndrome (28.6%), rheumatoid arthritis (21.4%), adult Still disease (14.3%) and dermatomyositis (7.1%). Infected organs were lung (85.7%), brain (42.9%), skin/cutaneous lesions (28.6%) and muscle (7.1%). Disseminated infections were seen in nine patients (64.3%). At the onset of nocardiosis, all patients were given prednisolone (23.2 ± 11.9 mg/day). Only two patients (14.3%) were given TMP-SMX for prophylaxis of pneumocystis pneumonia. Relapse occurred in one patient (7.1%) and four patients (28.6%) died from nocardiosis for a cumulative survival rate at 52 weeks of 76.9%. In a comparison of survivors (71.4%) and non-survivors (28.6%), cutaneous lesions were significantly more frequent in the latter (10 vs 75%, p = .04) with an odds ratio of 27.0 (95% CI: 1.7-453.4). CONCLUSION: Cutaneous lesions as a result of dissemination might be a risk factor for nocardiosis mortality in patients with CTDs.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Arthritis, Rheumatoid/complications , Lupus Erythematosus, Systemic/complications , Nocardia Infections/drug therapy , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Vasculitis/complications , Adult , Anti-Bacterial Agents/adverse effects , Female , Humans , Male , Middle Aged , Nocardia Infections/complications , Nocardia Infections/pathology , Prognosis , Retrospective Studies , Trimethoprim, Sulfamethoxazole Drug Combination/adverse effects
13.
ACS Med Chem Lett ; 11(6): 1335-1341, 2020 Jun 11.
Article in English | MEDLINE | ID: mdl-32551021

ABSTRACT

Lysophosphatidic acid (LPA) is a bioactive lipid mediator that elicits a number of biological functions, including smooth muscle contraction, cell motility, proliferation, and morphological change. LPA is endogenously produced by autotaxin (ATX) from extracellular lysophosphatidylcholine (LPC) in plasma. Herein, we report our medicinal chemistry effort to identify a novel and highly potent ATX inhibitor, ONO-8430506 (20), with good oral availability. To enhance the enzymatic ATX inhibitory activity, we designed several compounds by structurally comparing our hit compound with the endogenous ligand LPC. Further optimization to improve the pharmacokinetic profile and enhance the ATX inhibitory activity in human plasma resulted in the identification of ONO-8430506 (20), which enhanced the antitumor effect of paclitaxel in a breast cancer model.

14.
Intern Med ; 59(8): 1087-1091, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-31915317

ABSTRACT

Aortic arch aneurysm (AAA) is a rare involvement in Behçet disease (BD). It is often life-threatening, yet few reports related to the treatment of AAA have been published. We herein report a 27-year-old woman with AAA caused by vascular BD. She was initially treated with prednisolone 1 mg/kg/d. However, the inflammation had not subsided after three weeks, so infliximab (IFX) was added for relief. After IFX administration, the C-reactive protein level normalized, and computed tomography at three months after therapeutic intervention revealed that the aneurysm had disappeared. This case suggests that early induction of IFX might be effective for aortic aneurysm in BD.


Subject(s)
Aorta, Thoracic/pathology , Aortic Aneurysm/complications , Behcet Syndrome/complications , Behcet Syndrome/drug therapy , Infliximab/therapeutic use , Adult , Female , Humans , Tomography, X-Ray Computed , Treatment Outcome
15.
ACS Med Chem Lett ; 8(1): 107-112, 2017 Jan 12.
Article in English | MEDLINE | ID: mdl-28105284

ABSTRACT

A novel series of prostaglandin analogues with a seven-membered ring scaffold was designed, synthesized, and evaluated for the functional activation of prostaglandin receptors to identify potent and subtype-selective FP and EP3 dual agonists. Starting from the prostacyclin derivative 5b, a nonselective agonist for prostaglandin receptors, replacement of the core structure with an octahydro-2H-cyclopenta[b]oxepine scaffold led to the discovery of the potent and selective FP and EP3 dual agonist 11b as a lead compound for the development of an antiglaucoma agent.

16.
Mol Brain ; 9: 2, 2016 Jan 08.
Article in English | MEDLINE | ID: mdl-26745987

ABSTRACT

BACKGROUND: The conditions under which memory generalization occurs are not well understood. Although it is believed that fear memory generalization is gradually established after learning, it is not clear whether experiences soon after learning affect generalization. RESULTS: Using a contextual fear conditioning paradigm in mice, we found that fear memory generalization occurred when mice were exposed to a familiar, unconditioned context soon after fear learning. CONCLUSIONS: Our results suggest that the familiarity of contexts and the timing of their exposure influences memory generalization, which increases our understanding of the mechanisms of generalization.


Subject(s)
Fear/physiology , Generalization, Response/physiology , Memory/physiology , Animals , Mice, Inbred C57BL
17.
Chem Commun (Camb) ; 48(93): 11461-3, 2012 Dec 04.
Article in English | MEDLINE | ID: mdl-23091821

ABSTRACT

Positively charged photodegradable nanoparticles that simultaneously encapsulated various compounds including small and large molecules were prepared. The nanoparticles were internalized to the cell by endocytosis and were stable within the cells for at least 4 days. The encapsulated molecules were released into the cytosol using light stimuli.


Subject(s)
Endocytosis , Nanoparticles/chemistry , Capsules , Cell Line, Tumor , Drug Stability , Endocytosis/radiation effects , Humans , Light , Time Factors
18.
Bioorg Med Chem ; 20(2): 1122-38, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-22196514

ABSTRACT

To identify structurally novel corticotropin-releasing factor 1 (CRF(1)) receptor antagonists, a series of bicyclic core analogs pyrrolo[1,2-b]pyridazines and pyrrolo[2,1-f]triazin-4(3H)-ones, which were designed based on a monocyclic core antagonist, was synthesized and evaluated. Among the compounds tested, 2-difluoromethoxy-4-methylpyridin-5-yl analog 27 was found to show efficacy in a dose-dependent manner in an elevated plus maze test in rats. The discovery process and structure-activity relationship is presented.


Subject(s)
Anti-Anxiety Agents/chemistry , Anti-Anxiety Agents/pharmacology , Pyridazines/chemistry , Receptors, Corticotropin-Releasing Hormone/antagonists & inhibitors , Triazines/chemistry , Triazines/pharmacology , Animals , Anti-Anxiety Agents/chemical synthesis , Anti-Anxiety Agents/pharmacokinetics , Male , Protein Binding/drug effects , Rats , Rats, Sprague-Dawley , Receptors, Corticotropin-Releasing Hormone/metabolism , Structure-Activity Relationship , Triazines/chemical synthesis , Triazines/pharmacokinetics
19.
Biomed Chromatogr ; 25(6): 635-40, 2011 Jun.
Article in English | MEDLINE | ID: mdl-20812201

ABSTRACT

The derivatization reagents for carboxylic acids, N-(Pyridin-3-yl)hydrazinecarbothioamide, N-[4-(dimethylamino)phenyl]hydrazinecarbothioamide, 1-(2-aminoethyl)-3-(pyridin-3-yl)thiourea, 1-(2-aminoethyl)-3-[4-(dimethylamino)phenyl]thiourea and 4-(2-aminoethyl)-N-phenylpiperazine-1-carbothioamide were synthesized. These reagents reacted with carboxylic acids at 60°C for 45 min in the presence of the condensation reagents. The generated derivatives were favorably separated on the reversed-phase column and sensitively detected by electrospray ionization tandem mass spectrometry. These reagents enhanced the electrospray ionization response of the analyte and generated a particular product ion efficiently by collision-induced dissociation, and thus they were suitable for MS/MS detection.


Subject(s)
Carboxylic Acids/chemistry , Tandem Mass Spectrometry/methods , Thiourea/analogs & derivatives , Carboxylic Acids/analysis , Chromatography, Reverse-Phase , Indicators and Reagents/chemical synthesis , Indicators and Reagents/chemistry , Thiourea/chemical synthesis , Thiourea/chemistry
20.
Chemistry ; 16(2): 600-10, 2010 Jan 11.
Article in English | MEDLINE | ID: mdl-19937620

ABSTRACT

The first total synthesis of amino sugar antibiotic glycocinnasperimicin D (1) has been achieved by a convergent, three-component coupling strategy. The key steps involve the Heck-Mizoroki reaction by using the iodophenyl glycoside 50 and acryl amide 32 to furnish the right core structure of 1, and the construction of the urea glycoside employing the reaction of glycosyl isocyanate 8 with amino sugar 9. Glycosyl isocyanate 8 was prepared by the oxidation of isonitrile 10, which displayed excellent reactivity in the coupling event. Synthetic roadblocks, encountered during this synthetic effort, have led to the development of the alpha-selective, Lewis acid catalyzed phenyl glycosylation process with 2-amino-hexopyranose and a procedure for acetonide deprotection without affecting the silyl ethers.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Catalysis , Glycosylation , Molecular Structure , Spermidine/analogs & derivatives , Spermidine/chemical synthesis , Spermidine/chemistry , Stereoisomerism
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