Production of no-carrier-added 177Lu via the 176Yb(n, &;#947;)177Yb &;#8594; 177Lu process

No-carrier-added ¹⁷⁷Lu was produced by the ¹⁷⁶Yb(n,)¹⁷⁷Yb¹⁷⁷Lu process using enriched ¹⁷⁶Yb₂O₃. The radiochemical separation of the nca ¹⁷⁷Lu from the macroscopic ytterbium target was investigated by reversed-phase ion-pair HPLC. Effects of the concentrations of 2-hydroxyisobutyric acid and 1-octanesulfonate in the eluent, the amount of Yb₂O₃, the type and length of the C₁₈ column on the separation efficiency were examined. Under optimum conditions, the nca ¹⁷⁷Lu was obtained in radiochemically pure form from 5 mg of Yb₂O₃ with a separation yield of 84%.     

(±)-Malaysianone A和(±)-Tanariflavanones B的全合成

以取代苯乙酮和5-醛基-8-甲氧甲氧基-2-甲基-2-(4'-甲基-3'-戊烯基)-二氢-1-苯并吡喃为原料,经羟醛缩合反应制得两个中间体——7,2',4'-三甲氧甲氧基-6'-羟基-2-甲基-2-(4'-甲基-3'-戊烯基)-二氢-1-苯并吡喃查尔酮(3a)和7,2',4'-三甲氧甲氧基-5'-异戊烯基-6'-羟基-2-甲基-2-(4'-甲基-3'-戊烯基)-二氢-1-苯并吡喃查尔酮(3b);3a经环合和脱保护基反应合成了(±)-Malaysianone A(4a),产率12.9%;3b经脱保护基和环合反应合成了(±)-Tanariflavanones B(4b),产率5.2%。4a和4b的结构经1H NMR,13C NMR和HR-ESI-MS确证。     

Comparison of the efficacy of 177Lu-EDTMP, 177Lu-DOTMP and 188Re-HEDP towards bone osteosarcoma: an in vitro study

Among the radiopharmaceuticals harnessed for palliation of bone pain in osseous metastases patients, ¹⁷⁷Lu labeled phosphonates such as EDTMP (Ethylene diamine tetramethylene phosphonic acid) as well as DOTMP (1,4,7,10-tetraaza-cyclo-dodecane-1,4,7,10 tetraethylene phosphonic acid) and ¹⁸⁸Re-labeled HEDP (1,1-hydroxyethylene diphosphonic acid) seem to be the most favorable for treatment of small and medium/large size bone lesions, respectively. A comparative assessment of ¹⁷⁷Lu-EDTMP, ¹⁷⁷Lu-DOTMP and ¹⁸⁸Re-HEDP in osteosarcoma tumor cell line was carried out to evaluate their relative efficacy. It was found that ¹⁸⁸Re-HEDP is more potent in induction of cell toxicity and apoptosis compared to the ¹⁷⁷Lu-EDTMP and ¹⁷⁷Lu-DOTMP, thus ¹⁸⁸Re-HEDP might have great clinical significance.

     

TOTAL SYNTHESIS OF(±)LESPEDEZAFLAVANONE-A

Lespedezaflavanone-A(1)was a new isoprene substituted flavanone which was isolated from, the root bark of Lespedeza davidii.In this paper, the total synthesis of its racemate(±)-1 was reported.     

Gas adsorption and storage in metal-organic framework MOF-177

Gas adsorption experiments have been carried out on a zinc benzenetribenzoate metal-organic framework material, MOF-177. Hydrogen adsorption on MOF-177 at 298 K and 10 MPa gives an adsorption capacity of approximately 0.62 wt %, which is among the highest hydrogen storage capacities reported in porous materials at ambient temperatures. The heats of adsorption for H2 on MOF-177 were -11.3 to -5.8 kJ/mol. By adding a H2 dissociating catalyst and using our bridge building technique to build carbon bridges for hydrogen spillover, the hydrogen adsorption capacity in MOF-177 was enhanced by a factor of approximately 2.5, to 1.5 wt % at 298 K and 10 MPa, and the adsorption was reversible. N2 and O2 adsorption measurements showed that O2 was adsorbed more favorably than N2 on MOF-177 with a selectivity of approximately 1.8 at 1 atm and 298 K, which makes MOF-177 a promising candidate for air separation. The isotherm was linear for O2 while being concave for N2. Water vapor adsorption studies indicated that MOF-177 adsorbed up to approximately 10 wt % H2O at 298 K. The framework structure of MOF-177 was not stable upon H2O adsorption, which decomposed after exposure to ambient air in 3 days. All the results suggested that MOF-177 could be a potentially promising material for gas separation and storage applications at ambient temperature (under dry conditions or with predrying).     

Production of 177Lu by neutron activation of 176Lu

Production of the radiopharmaceutical nuclide ¹⁷⁷Lu, by direct thermal neutron activation of ¹⁷⁶Lu, poses a discrepancy between experimentally measured and theoretically predicted activities. It was found that in the irradiation at the pneumatic transfer tube (Rabbit) of the IRR-1 reactor, the exper./theor. ratio was 1.858± 0.051. This ratio was determined also by comparing the activities of ¹⁷⁷Lu and ^176mLu. The significant deviation of ¹⁷⁶Lu from the 1/v behavior explained this disagreement. The ratio exper./theor. is the Westcott g(T _n)-factor and was used to yield the neutron temperature T _n = 311±8 K.The assistance of Eyal Elish in performing the ICP-MS analyses of Lu is gratefully acknowledged.     

Facile preparation of 177Lu-microspheres for hepatocellular carcinoma radioisotope therapy

As one of the most common cancers in the world, hepatocellular carcinoma (HCC) has become a major threat to human health. Radioembolization is a first-line option for the treatment of HCC, especially when other conventional treatments fail or there exist some relative contraindications. Herein, we developed a facile and efficient method for preparing ¹⁷⁷Lu-microspheres potentially useful for precise radioembolization therapy of HCC. The radiolabeling efficiency of ¹⁷⁷Lu-microspheres was as high as 96.8% ± 0.5%, and the radiolabeling process did not alter the morphology of the mother microspheres. The SPECT/CT studies enabled by the unique emissions of ¹⁷⁷Lu suggested that almost no ¹⁷⁷Lu ion loaded by the microspheres was released over more than 32 d in vivo, which led to remarkable inhibition effect on the growth of HepG2 tumors subcutaneously transplanted in mice. The current approach may thus offer promising ¹⁷⁷Lu-microspheres for clinical radioembolization of HCC.     

Production of 177Lu by neutron activation of 176Lu

Production of the radiopharmaceutical nuclide ¹⁷⁷Lu, by direct thermal neutron activation of ¹⁷⁶Lu, poses a discrepancy between experimentally measured and theoretically predicted activities. It was found that in the irradiation at the pneumatic transfer tube (Rabbit) of the IRR-1 reactor, the exper./theor. ratio was 1.858± 0.051. This ratio was determined also by comparing the activities of ¹⁷⁷Lu and ^176mLu. The significant deviation of ¹⁷⁶Lu from the 1/v behavior explained this disagreement. The ratio exper./theor. is the Westcott g(T _n)-factor and was used to yield the neutron temperature T _n = 311±8 K.The assistance of Eyal Elish in performing the ICP-MS analyses of Lu is gratefully acknowledged.     

Stoffwechselprodukte von Mikroorganismen. 177. Mitteilung. Avilamycin C

From cultures of the Avilamycin (Avilamycin A) producing organism, Streptomyces viridochromogenes, strain ETH 23575, a second antibiotic, Avilamycin C, C₆₁H₉₀Cl₂O₃₂ could be isolated in crystalline form. Both Avilamycins belong to the group of the Orthosomycins. By IR., ¹H- and ¹³C-NMR. spectroscopy and by transformation to a common derivative it could be proven that Avilamycin A is a methyl ketone, Avilamycin C the corresponding methyl carbinol.     

Alternative chromatographic processes for no-carrier added 177Lu radioisotope separation

HPLC technique combined with the simple conventional column solid phase extraction (SPE) chromatography using di-(2-ethylhexyl)orthophosphoric acid (HDEHP) impregnated OASIS-HLB sorbent based SPE resins (OASIS-HDEHP) was developed for the separation of no-carrier added (n.c.a) ¹⁷⁷Lu from the bulk quantity of ytterbium target. This combination strategy was based on combining the advantages of the better resolution of HPLC separation of n.c.a ¹⁷⁷Lu from the few milligram level Yb target with the high capacity of the OASISHDEHP column for the separation of ¹⁷⁷Lu from the bulk Yb target. The production batches of several hundred mCi activity of n.c.a ¹⁷⁷Lu radioisotope separated from 50 mg Yb target activated in a nuclear reactor of medium neutron flux (Φ=5·10¹³ n·cm^?2·s^?1) were successfully performed using this combined separation technique. With the target irradiation in a reactor of higher thermal neutron flux or with the parallel run of several separation units, several Ci-s of n.c.a ¹⁷⁷Lu can be profitably produced on a commercial production basis.     

First Total Synthesis of the (±)-Preverecynarmin

The preverecynarmin(12), (+)-(1E,3E,7E,11E)-cembra-3,7,11-tetraen-6yl acetate,was first isolated in 1990 from both Armina maculata and its prey,the pennatulacean coral Veretillum cynomorium with other there briarane diferpenoids and cembene-C((1E,3E,7E,11E)-cembra-l,3,7,11-tetraen¹. As far as we known, the bioactive test and total synthesis of ¹² have not been reported yet. Herein we wish to describe the first total synthesis of (±)-preverecynarmin (12).     

Separation of carrier-free lutetium-177 from neutron irradiated natural ytterbium target

Neutron irradiation of naturally occurring Yb produces small amounts of carrier-free¹⁷⁷Lu activity. Cation exchange chromatography in the displacement development mode using Dowex-50X8, 200–400 mesh resin, and Zn²⁺ as the separating ion was used to separate¹⁷⁷Lu produced in a neutron irradiated Yb target. 0.04M -hydroxyisobutyric acid at pH 4.6±2 and temperature 26±1°C was used to elute carrier-free¹⁷⁷Lu in 70% yield and at a radionuclidic purity greater than 99%.     

Electrochemical method for producing radionuclide Lu-177 with high specific activity

A modified method for the isolation of radionuclide ¹⁷⁷Lu obtained from a Yb-176 target irradiated with thermal neutrons is proposed. The method consists of the combination of two electrochemical processes— cementation of ytterbium acetate–chloride solution to sodium amalgam and subsequent electrolysis of the ytterbium solution in a separate electrolytic cell without adjusting the solution. The electrochemical setup consisting of two cells gives the purification factor of ¹⁷⁷Lu from ytterbium at a level of 10⁵–10⁶, which allows using ¹⁷⁷Lu of such quality for labeling bioorganic molecules.     

Pt@MOF-177: synthesis, room-temperature hydrogen storage and oxidation catalysis

The gas-phase loading of [Zn(4)O(btb)(2)](8) (MOF-177; H(3)btb=1,3,5-benzenetribenzoic acid) with the volatile platinum precursor [Me(3)PtCp'] (Cp'=methylcyclopentadienyl) was confirmed by solid state (13)C magic angle spinning (MAS)-NMR spectroscopy. Subsequent reduction of the inclusion compound [Me(3)PtCp'](4)@MOF-177 by hydrogen at 100 bar and 100 degrees C for 24 h was carried out and gave rise to the formation of platinum nanoparticles in a size regime of 2-5 nm embedded in the unchanged MOF-177 host lattice as confirmed by transmission electron microscopy (TEM) micrographs and powder X-ray diffraction (PXRD). The room-temperature hydrogen adsorption of Pt@MOF-177 has been followed in a gravimetric fashion (magnetic suspension balance) and shows almost 2.5 wt % in the first cycle, but is decreased down to 0.5 wt % in consecutive cycles. The catalytic activity of Pt@MOF-177 towards the solvent- and base-free room temperature oxidation of alcohols in air has been tested and shows Pt@MOF-177 to be an efficient catalyst in the oxidation of alcohols.     

Production of 177Lu by hafnium irradiation using 55-MeV bremsstrahlung photons

Journal of Radioanalytical and Nuclear Chemistry - The possibility of production a medical radionuclide 177Lu by irradiating natHfO2 by bremsstrahlung photons up to 55 MeV was...     

The Total Synthesis of (±)-13-Hydroxyneocembrene

(13S)-hydroxyneocembrene(18), a cembranoid which was isolated in 1988 from soft coral Sarcophyton trocheliophorum¹, has been shown to be an effective inductor of the release of labeled glucose from the lecithincholesterol liposomes and have cytostatic activities². The geometrical structure and absolute configuration of 18 have been defined to be 1S, 2E, 7E, 11E, 13S. Herein, we report the total synthesis of (±)-13hydroxyneocembrene(18).