Toward Efficient Synthesis of Chiral Zeolites: A Rational Strategy for Fluoride-Free Synthesis of STW-Type Zeolite

The STW-type zeolite is attractive for developing novel enantioselective syntheses/separation of chiral compounds because it is the only chiral zeolitic microporous material whose enantioenriched synthesis has been achieved. In addition to the conventional industries in which zeolites are used, STW should have diverse industrial applications in the pharmaceutical and food industries. However, the toxic and caustic fluoride required for synthesizing STW severely hinders its commercialization by mass production. Herein, we report the first example of fluoride-free STW synthesis, in which the two roles of fluoride-formation of a zeolitic framework rich in tetravalent T-atoms and promotion of double 4-membered ring unit formation-were substituted by dry gel conversion and Ge addition, respectively. The STW obtained was highly crystalline, with a similar micropore volume and thermal stability as those of original fluoride-based STW. Our approach is promising not only for the fluoride-free synthesis of enantiomeric STW but also for general fluoride-free syntheses.

Ultrafast Encapsulation of Metal Nanoclusters into MFI Zeolite in the Course of Its Crystallization: Catalytic Application for Propane Dehydrogenation

Encapsulating metal nanoclusters into zeolites combines the superior catalytic activity of the nanoclusters with high stability and unique shape selectivity of the crystalline microporous materials. The preparation of such bifunctional catalysts, however, is often restricted by the mismatching in time scale between the fast formation of nanoclusters and the slow crystallization of zeolites. We herein demonstrate a novel strategy to overcome the mismatching issue, in which the crystallization of zeolites is expedited so as to synchronize it with the rapid formation of nanoclusters. The concept was demonstrated by confining Pt and Sn nanoclusters into a ZSM-5 (MFI) zeolite in the course of its crystallization, leading to an ultrafast, in situ encapsulation within just 5 min. The Pt/Sn-ZSM-5 exhibited exceptional activity and selectivity with stability in the dehydrogenation of propane to propene. This method of ultrafast encapsulation opens up a new avenue for designing and synthesizing composite zeolitic materials with structural and compositional complexity.

Multi-objective de novo molecular design of organic structure-directing agents for zeolites using nature-inspired ant colony optimization

Organic structure-directing agents (OSDAs) are often employed for synthesis of zeolites with desired frameworks. A priori prediction of such OSDAs has mainly relied on the interaction energies between OSDAs and zeolite frameworks, without cost considerations. For practical purposes, the cost of OSDAs becomes a critical issue. Therefore, the development of a computational de novo prediction methodology that can speed up the trial-and-error cycle in the search for less expensive OSDAs is desired. This study utilized a nature-inspired ant colony optimization method to predict physicochemically and/or economically preferable OSDAs, while also taking molecular similarity and heuristics of zeolite synthesis into consideration. The prediction results included experimentally known OSDAs, candidates having structures closely related to known OSDAs, and novel ones, suggesting the applicability of this approach.

Inspired by the exploratory methods of ant colonies, adaptive optimization was employed to explore the chemical space for organic molecules that guide zeolite crystallization, giving both physicochemically and economically promising molecules.

Superior Ion-exchange Property of Amorphous Aluminosilicates Prepared by a Co-precipitation Method

The development of inexpensive inorganic ion-exchangers for the purification of environmental pollutants is a social demand. Amorphous aluminosilicates with a relatively high homogeneous Al environment are prepared by a feasible co-precipitation method, i. e., mixing an acidic aluminum sulfate solution and basic sodium silicate solution, which exhibit excellent ion-exchange selectivity for Cs⁺ and Sr²⁺ . The K_d value for Sr²⁺ was comparable with that of zeolite 4A. The local structures and ion-exchange behavior of the amorphous aluminosilicates are systematically investigated. The ion-exchange property of the amorphous aluminosilicates can be tuned by changing the interaction between the exchangeable cation and the amorphous aluminosilicates. Also, the amorphous aluminosilicates can adsorb bulky cations that zeolites hardly adsorb due to the limitation of the miropore size of zeolites.

SAT0146 INHIBITION OF RADIOGRAPHIC PROGRESSION BY IGURATINOD IN 116 JAPANESE RHEUMATOID ARTHIRITIS PATIENTS DESPITE CONVENTIONAL SYNTHETIC DISEASE-MODIFYING ANTIRHEUMATIC DRUGS THERAPY

Background:

Japanese double-blind clinical practice studies of Iguratimod (IGU) for active rheumatoid arthritis (RA) patients indicated an early and sustained efficacy as a new conventional synthetic disease-modyfing anti-rheumatic drugs (csDMARDs) [1] as well as the safety of the treatment[2]. IGU also inhibit activation of NFkB and production of RANKL, indicating strong inhibiting activity against bone destruction. However, studies focused on the inhibitory effects of joint destruction by IGU has been poorly documented in clinical practice (3).

Objectives:

To evaluate inhibitory effect during 1 year by additional IGU therapy in 116 RA patients despite csDMARDs therapy.

Methods:

Inhibitory effects of joint damage were evaluated by modified total Sharp scoring (mTSS) at baseline and 1 year after IGU prescription. RA activity was measured by DAS28-ESR.

Results:

The subjects were 116 cases, 30 male, age 63.2 yrs, disease duration 93.7 months. MTX was used weekly (84 cases, 72.4%), and cs DMARDs were used as BUC 43 cases, SASP 13 cases, TAC 5 cases, and LEF 1 cases. bDMARDs were used even in 8 cases, and steroids were used in 3.9 mg (70 cases, 60.3 %). Complications were observed in 70 cases (60.3%). DAS28-ESR were significantly improved from 4.29 (baseline) to 3.65 (6 months), 3.68 (12 months), respectively (P<0.0001). As shown in Figure 1, joint destruction measured by mTSS was significantly suppressed from 7.74 to 0.57 at 1 year (P<0.0001). 70.6% of patients satisfied structural remission (ΔmTSS≤0.5). Clinically relevant radiographic progression (CRRP)(mTSS>3) was observed in 10 cases (8.6%), and rapid radiographic progression(RRP) (mTSS≥5) was observed in 2 cases (1.6%). Adverse events were observed in 26 cases (22.4 %).

To investigate prognostic factor for CRRP, clinical data in baseline, 6, 12 months between ten patients with CRRP and 82 patients with structural remission were compared. As shown in Table 1, longer disease duration, more SJC (P<0.05), High CRP level(P<0.005) were prognostic for CRRP in IGU treated patients.

Conclusion:

Iguratimod suppressed not only clinical activities but also joint destruction in RA patients resistant to csDMARDs therapy.

Table 1. Prognostic factor for CRRP

References:

[1]Ishiguro N, Yamamoto K, Katayama K et al. Concomitant iguratimod therapy in patients with active rheumatoid arthritis despite stable doses of methotrexate a randomized, double-blind, placebo-controlled trial. Mod Rheumatol. 2013;23(3):430-9

[2]Hara M, Ishiguro N, Katayama K et al. Safety and efficacy of combination therapy of iguratimod with methotrexate for patients with active rheumatoid arthritis with an inadequate response to methotrexate: an open-level extension of a randomized, double-blind, placebo-controlled trial. Mod Rheumatol. 2014;24(3):410–8.

[3]Ishikawa K, Ishikawa J.Iguratimod, a synthetic disease modifying anti-rheumatic drug inhibiting the activation of NF-jB and production of RANKL: Its efficacy, radiographic changes,safety and predictors over two years’ treatment for Japanese rheumatoid arthritis patients. Mod.Rheumatol.2019,29(3), 418–429.

Disclosure of Interests:

None declared

FRI0127 Suppression of radiographic progression after gradual methotrexate tapering in patients with rheumatoid arthritis patients maintaining low disease activity - Prospective multicenter study-

Background:

Many studies have been reported to reduce/discontinue Biologics in the treatment of rheumatoid arthritis (RA). In contrast, study for tapering methotrexate (MTX) has been limited (1,2).

Objectives:

We prospectively examined whether bone destruction will progress at 48 weeks after tapering or discontinuing MTX (UMIN000028875).

Methods:

The subjects were RA patients who have maintained low disease activity or lower for 24 weeks or more in DAS28-CRP after MTX administration. Patients having PDUS Grade 2 or 3 per site by bilateral hand ultrasonography (26 area) were excluded in this study owing to risk for joint destruction. The joint destruction was evaluated by the joint X-ray evaluation by modified total Sharp scoring (mTSS) at 1 year after the start of tapering MTX. Evaluation of clinical disease activities, severe adverse events, the continuation rate during MTX tapering were also evaluated. According to tapering response, prognostic factor for good response for tapering, joint destruction was determined. Predictors for successful tapering MTX and progression of bone destruction were determined. Statistical analysis was performed by t-test or Wilcoxon rank sum test using SAS .13.2 software.

Results:

The subjects were 79 (16 males, 63 females). Age average 60.9 years, disease duration 4 years 4 months, MTX dose 8.43 mg / w, DAS28-CRP 1.52, DMARDs (24.3%), ACPA 192.7 U / ml (70.5%), RF 55.6 IU / ml (65.4%).MTX was tapered from an average of 8.43 mg / w before study to 5.46 mg / w one year later. In the treatment evaluation, DAS28-CRP increased from 1.52 to 1.84. 89.7% of subjects did not progress joint damage. Other disease activities significantly increased (Table 1). The one-year continuation rate was 78.2%. Since tapering effects were varied widely, we divided patients into three groups; Flared group (N=14, initial MTX dose 8.71mg/w, final MTX dose 8.42mg/w), Low response group (N=31, final MTX reduction rate< 50%, initial MTX dose 8.93mg/w, final MTX dose 6.22mg/w), High response group (N=34, final MTX reduction rate≥ 50%, initial MTX dose 8.5mg/w, final MTX dose 3.15mg/w)(Table 2).Higher RF value at baseline and higher MTX dose at 3M, 6M were predictors of whether a subject was in Low response group or High Response group. Higher RF value and mTSS at baseline and higher MTX dose at 6M were predictors whether a subject was in Flared group or High response group. Lower age was predictor of whether a subject was in Flared group or Low responder group. Finally, mean ΔmTSS /y in Flared group (0.36) was not significantly higher than in low response group (0.07) and in high response group (0.01).

Table 1Table 2.

Predictors for successful tapering MTX and progression of bone destruction

Conclusion:

Patients with MTX-administered low disease activity and finger joint echo PDUS grade 1 satisfy almost no joint destruction even after MTX reduction. For tapering, predictors may be helpful for maintaining patient’s satisfaction.

References:

[1]Baker KF, Skelton AJ, Lendrem DW et al. Predicting drug-free remission in rheumatoid arthritis: A prospective interventional cohort study. J. Autoimmunity. 2019;105: 102298.

[2]Lillegraven S, Sundlisater N, Aga A et al. Tapering of Conventional Synthetic Disease Modifying Anti-Rheumatic Drugs in Rheumatoid Arthritis Patients in Sustained Remission: Results from a Randomized Controlled Trial. American College of Rheumatology. 2019; Abstract L08.

Disclosure of Interests:

None declared

AB0298 LONG-TERM SUPPRESSION OF RAPID RADIOGRAPHIC PROGRESSION AFTER DISCONTINUATION/REDUCTION OF SHORT-TERM BIOLOGIC THERAPY IN PATIENTS WITH EARLY DESTRUCTIVE RHEUMATOID ARTHRITIS ACCOMPANIED WITH EXTENSIVE BONE MARROW EDEMA

Background:

We reported that short-term (3 or 6 months) treatment with biologics (BIO) group compared with conventional synthetic non-biological disease-modifying anti rheumatic drug (csDMARDs) enhanced group is more effective in the reducing bone marrow edema (BE) and improving structural remission in early destructive RA accompanied with extensive hand BM despite csDMARDs therapy (1).

Objectives:

Purpose of this extended study is to investigate whether suppression of RRP will maintain after the discontinuation/reduction of short term biological treatment during over 1 year. Clinical registration number; (UMIN-CTR 000013614)(Figure 1)

Methods:

RA disease activity was evaluated by DAS28-ESR after BIO withdrawal/reduction at 12 months. Bone destruction was determined by modified total Sharp scoring (mTSS) using by conventional radiography expressed as yearly progression of mTSS (ΔmTSS/y) at 12 months. Statistical analysis were performed by t-test or Wilcoxon rank sum test using SAS .13.2 software

Results:

Fourteen out of 23 patients in BIO group achieved improvement of BM (>70% improvement of baseline BE). Three patient continued BIO. Among 11 patient started to discontinuation/reduction of BIO, 7 patients were successful for discontinuation of BIO. Four patients flared (Table 1). Mean DAS28-ESR, mean ΔmTSS/y at 0, 12 months after discontinuation in 7 patients were 1.77, 2.02 and -0.66,-0.44, respectively (no significant difference between values in 0 and12 month). In contrast, those in 4 flared patients were 1.91, 4.08 and 0, 1.83, respectively (significant difference). Finally, to resolve baseline prognostic factors for improvement of BE for biological treatment, we compared baseline data between 14 BE improved and 9 BE unimproved RA patients. Low DAS28-ESR at 3 or 6 month (P<0.001) are indicated for significant prognostic factor for improvement of BE, although Low DAS28-ESR at baseline (P=0.07) may associate improvement of BE.

Table 1.

Summary of 1 year clinical data in 11 patients treated in BIO discontinuation/reduction after improvement of BE by short-term treatment of BIO

Conclusion:

Results of this study indicated suppression of RRP will maintain during over 1 year after the discontinuation of short term biological treatment in some patients. We recommend that a short-term treatment with biologics for early RA patients, who are resistant to non-bio DMARDs therapy and at high risk to transit to RRP, will be an effective and economical treatment strategy.

References:

[1]K. Katayama, T. Okubo, S. Sato et al. Prevention of extensive bone marrow edema and consequent rapid radiographic progression by short term usage of biologics in DMARDs resistant patients with early destructive rheumatoid arthritis. EULAR meeting. FRI 0124(2018).

Disclosure of Interests:

None declared

Extremely Stable Zeolites Developed via Designed Liquid-Mediated Treatment

Improving the stability of porous materials for practical applications is highly challenging. Aluminosilicate zeolites are utilized for adsorptive and catalytic applications, wherein they are sometimes exposed to high-temperature steaming conditions (∼1000 °C). As the degradation of high-silica zeolites originates from the defect sites in their frameworks, feasible defect-healing methods are highly demanded. Herein, we propose a method for healing defects to create extremely stable high-silica zeolites. High-silica (SiO₂/Al₂O₃ > 240) zeolites with *BEA-, MFI-, and MOR-type topologies could be stabilized by significantly reducing the number of defect sites via a liquid-mediated treatment without using additional silylating agents. Upon exposure to extremely high temperature (900-1150 °C) steam, the stabilized zeolites retain their crystallinity and micropore volume, whereas the parent commercial zeolites degrade completely. The proposed self-defect-healing method provides new insights into the migration of species through porous bodies and significantly advances the practical applicability of zeolites in severe environments.

Water-Dispersible Triplet-Triplet Annihilation Photon Upconversion Particle: Molecules Integrated in Hydrophobized Two-Dimensional Interlayer Space of Montmorillonite and Their Application for Photocatalysis in the Aqueous Phase

Green incident light (λ = ∼500 nm) is converted to blue light (λ = 400-450 nm) in air using bulky alkylammonium (DMDOA⁺), 9,10-diphenylanthracene (DPA), and Ru(dmb)₃²⁺ (dmb = 4,4'-dimethyl-2,2'-bipyridine) intercalated in a layered clay compound called "montmorillonite" [MMT-DMDOA⁺-DPA-Ru(dmb)₃²⁺]. The two-dimensional interstitial space has an interlayer spacing of a few nanometers. Emitter DPA is present in this interlayer spacing, having an intermolecular distance of approximately 3.0 nm at a high concentration. Sensitizer Ru(dmb)₃²⁺ is relatively dilute, having an intermolecular distance of 47 nm. The emission decay measurements and quantitative evaluation of the emission intensity demonstrate that blue light emission is induced by sequential processes, which consist of a triplet-triplet (T-T) energy transfer reaction from Ru(dmb)₃²⁺ to DPA and T-T annihilation of DPA molecules. From thermogravimetry and Fourier transform infrared spectra measurements, we observe that the cointercalated alkylammonium acts as a waterproof agent to prevent quenching of the molecules in the excited triplet states by H₂O. Finally, we demonstrate a photocatalytic decomposition of Rhodamine B dissolved in H₂O-containing MMT-DMDOA⁺-DPA-Ru(dmb)₃²⁺ and Pt-deposited WO₃ photocatalyst, where wavelength of incident light (λ > 440 nm) is longer than the absorption edge of WO₃ photocatalyst. The mechanism of photocatalytic decomposition is the following: (i) the incident long wavelength light is upconverted to 400-450 nm light by MMT-DMDOA⁺-DPA-Ru(dmb)₃²⁺, and then, (ii) WO₃ photocatalyst is excited by the generated 400-450 nm light, and finally, (iii) Rhodamine B is decomposed on the Pt cocatalyst induced by the holes in a valence band of WO₃.

Unique crystallization behavior in zeolite synthesis under external high pressures

Hydrothermal synthesis of zeolites under external high pressures generates unique crystallization behaviors that are different from the synthesis under autogenous pressure.

Optimized ultrafast flow synthesis of CON-type zeolite and improvement of its catalytic properties

The fast synthesis of CON-type zeolite could be an option for mass production using a continuous flow synthesis system.

Bridging the Gap between Structurally Distinct 2D Lamellar Zeolitic Precursors through a 3D Germanosilicate Intermediate

There is broad scientific interest in lamellar zeolitic materials for a large variety of technological applications. The traditional synthetic methods towards two-dimensional (2D) zeolitic precursors have made a great impact in the construction of families of related zeolites; however, the connection between structurally distinct 2D zeolitic precursors is much less investigated in comparison, thereby resulting in a synthetic obstacle that theoretically limits the types of zeolites that can be constructed from each layer. Herein, we report a Ge-recycling strategy for the topotactic conversion between different 2D zeolitic precursors through a three-dimensional (3D) germanosilicate. Specifically, the intermediate germanosilicate can be constructed within 150 min by taking advantage of its structural similarity with the parent lamellar precursor. This process enables the conversion of one 2D zeolite structure into another distinct structure, thus overcoming the synthetic obstacle between two families of zeolitic materials.

Bioinspired Approach to Silica Nanoparticle Synthesis Using Amine-Containing Block Copoly(vinyl ethers): Realizing Controlled Anisotropy

Core-shell polymer-silica hybrid nanoparticles smaller than 50 nm in diameter were formed in the presence of micelles of poly(2-aminoethyl vinyl ether-block-isobutyl vinyl ether) (poly(AEVE_m-b-IBVE_n)) through the hydrolysis and polycondensation of alkoxysilane in aqueous solution at a mild pH and temperature. The size of the nanoparticles as well as the number and size of the core parts were effectively controlled by varying the molecular weight of the copolymers. The polymers could be removed by calcination to give hollow silica nanoparticles with Brunauer-Emmett-Teller surface areas of more than 500 m² g^-1. Among these, silica nanoparticles formed with poly(AEVE₁₁₅-b-IBVE₄₀) displayed an anisotropy of single openings in the shell. The use of an alternative copolymer, poly(AEVE-b-2-naphthoxyethyl vinyl ether) (poly(AEVE₁₁₃-b-βNpOVE₄₀)), yielded core-shell nanoparticles with less pronounced anisotropy. These results showed that the degree of anisotropy could be controlled by the rigidity of micelles; the micelle of poly(AEVE₁₁₅-b-IBVE₄₀) was more deformable during silica deposition than that of poly(AEVE₁₁₃-b-βNpOVE₄₀) in which aromatic interactions were possible. This bioinspired, environmentally friendly approach will enable large-scale production of anisotropic silica nanomaterials, opening up applications in the field of nanomedicine, optical materials, and self-assembly.

Tracking the rearrangement of atomic configurations during the conversion of zeolite to zeolite

In order to realize designed synthesis, understanding the formation mechanism of zeolites at an atomic level has long been aspired, but remains challenging due to the fact that the knowledge of atomic configurations of the species formed during the process is limited. We focus on a synthesis system that crystallizes CHA zeolite from FAU zeolite as the sole source of tetrahedral atoms of Si and Al, so that end-to-end characterization can be conducted. Solid-state ²⁹Si MAS NMR is followed by high-throughput computational modeling to understand how atomic configurations changed during the interzeolite conversion. This reveals that the structural motif commonly found in FAU and CHA is not preserved during the conversion; rather, there is a specific rearrangement of silicates and aluminates within the motif. The atomic configuration of CHA seems to be influenced by that of the starting FAU, considering that CHA synthesized without using FAU results in a random Al distribution. A Metropolis Monte-Carlo simulation combined with a lattice minimization technique reveals that CHA derived from FAU has energetically favorable, biased atomic locations, which could be a result of the atomic configurations of the starting FAU. These results suggest that by choosing the appropriate reactant, Al placement could be designed to enhance the targeted properties of zeolites for catalysis and adsorption.

A series of magnon crystals appearing under ultrahigh magnetic fields in a kagomé antiferromagnet

Geometrical frustration and a high magnetic field are two key factors for realizing unconventional quantum states in magnetic materials. Specifically, conventional magnetic order can potentially be destroyed by competing interactions and may be replaced by an exotic state that is characterized in terms of quasiparticles called magnons, the density and chemical potential of which are controlled by the magnetic field. Here we show that a synthetic copper mineral, Cd-kapellasite, which comprises a kagomé lattice consisting of corner-sharing triangles of spin-1/2 Cu2+ ions, exhibits an unprecedented series of fractional magnetization plateaus in ultrahigh magnetic fields of up to 160 T. We propose that these quantum states can be interpreted as crystallizations of emergent magnons localized on the hexagon of the kagomé lattice.

Insights into the ion-exchange properties of Zn(ii)-incorporated MOR zeolites for the capture of multivalent cations

Understanding the properties of zeolites for cation exchange is important because the ion-exchange performance largely determines their suitability in applications such as catalysis and adsorptive separation. We synthesized a Zn(ii)-incorporated mordenite-framework aluminosilicate zeolite (Zn,Al-MOR), in which both Zn and Al are substituted in the framework, and studied its ion-exchange behavior for multivalent cations. For comparison, the original aluminosilicate mordenite (Al-MOR) was also synthesized with a composition adjusted to ensure that its charge density was similar to that of Zn,Al-MOR. While the incorporation of Zn(ii) led to a slower kinetic process, the selectivities and the exchange capacities toward multivalent cations (especially divalent cations) were significantly improved. Herein, we discussed the mechanism responsible for improving the ion-exchange performance in the presence of Zn(ii) and found that the incorporation of Zn(ii) led to a significant improvement in the ion-exchange temperature dependence of the MOR, which led to the ability to enhance ion-exchange capacity through temperature control during actual application. It was also revealed that the presence of Zn(ii) significantly improves selectivity and spontaneity toward the exchange of multivalent cations, Ni2+. Moreover, XRD and nitrogen-adsorption/desorption analyses revealed that the structures of the materials are maintained during the ion exchange, which is indicative of superior structural stability and tolerance to ion exchange.

Ultrafast synthesis of zeolites: breakthrough, progress and perspective

An ultrafast route was established to synthesize industrially important zeolites in several minutes, which represents a breakthrough in the field of zeolite synthesis.