A new series of cobalt(III) complexes of the type [Co(H2biim)n(en)3−n]3+ (H2biim = 2,2′-biimidazole; n = 1—3) was obtained. All of the complexes were resolved into their antipodes by SP-Sephadex column chromatography. The absorption, circular dichroism, and 1H NMR spectra of the complexes in aqueous solutions were dependent on the pH due to deprotonation of the imino protons of H2biim. The pKa1 and pKa2 values for [Co(H2biim)(en)2]3+ were obtained as 5.9 and 9.9, respectively, from the absorption spectra in aqueous solutions. The optically active deprotonated complexes, (−)589-[Co(Hbiim)3]·2H2O and (−)589-Ba1.5[Co(biim)3]·2H2O, were also isolated from weakly and strongly basic aqueous solutions, respectively, of (−)589-[Co(H2biim)3](NO3)3·H2O.

ABSTRACT:An attempt was made for quantitative synthesis of segmented poly(urethane-urea)s (PUUs), not via solution state, but directly from an isocyanate-terminated prepolymer prepared from an excess molar concentration of 4,4'-methylenediphenyldiisocyanate with poly(tetramethyleneoxide) (M.=2010) and reaction products from acetone and ethylenediamine (EDA) consisting of N-isopropylideneethylenediamine (I), N,N'-diisopropylideneethylenediamine (2), 2,2-dimethylimidazolidine (3) as main product, water, and the unreacted raw materials. With increasing the masking ratio of acetone to EDA, the concentrations of the ketimine groups and water increase while those of the imidazolidine and EDA generally decrease, the molar fraction of the by-product from the reaction of an isocyanate group with water was increased mainly because of the catalytic effect of the ketimine groups. Acetic acid played the significant roll to eliminate the side reaction by accelerating disappearance rate of (I) ((2)) and the quantitative yield of PUU was attained at 40°C when the acid concentration and the masking ratio were 3.50 x 10-3 mo! kg-1 and 1.4, respectively.KEY WORDS Poly(urethane-urea)s / Bulk Polymerization / Quantitative Yield/ Isocyanate-Terminated Prepolymer / Masked Diamines /Water/ Acid/ Segmented poly(urethane-urea)s (PUUs) compose of a class of elastomers exhibiting superior extensibility, toughness and durability over segmented poly(urethane)s and are extensively used in the fields from textile fibers to medical prosthesis.

ABSTRACT:An attempt was made to clarify the mechanism of the reactions of acetone with propylenediamine (PDA) or ethylenediamine (EDA) for direct synthesis of poly(urethane-urea) (DSPUU reaction) by using the reaction products (masked diamines) and an isocyanate-terminated prepolymer. In the masking reaction of acetone with PDA at 40°C, 1-(N-isopropylidene )propanediamine (1), 2-(N-isopropylidene )propanediamine (l '), 2,2-dimethyl-4-methylimidazolidine (3) as main product, N,N' -diisopropylidenepropylenediamine (2) were formed in this order due to the dominant rate (k 30 = 3.0kgmol-1 min -1 ) of the water-catalyzed reaction to form (3) in addition to the slow rate (k20 = 3.2 x 10-3 kgmol-1 min-1 ) of (2). The concentration of (l ') remained lower than (1) because of the steric hindrance of the methyl group of the former. The formation reactions of (1) and (2) were more acid-catalyzed than the reverse reactions, leading to shorter equilibrated time and larger molar fractions of these compounds. The reaction profiles for acetone-EDA were analogous except for lower molar fraction of 2,2-dimethylimidazolidine (6) and larger N,N'-diisopropylideneethylenediamine. The rates of demasking reactions which are of importance in DSPUU reactions using masked ED As were as follows; (i) the water-and acid-catalyzed ring opening reaction rate of (6), k _ 30 and k_ 3 = 1.43 and 0.26 kg mo!-1 min -, and (ii) the acid-catalyzed hydrolysis reaction rates of the ketimine groups, k_ 1 = 5.09 and k_ 2 =3.13kg 2 mo1-2 min-1 , respectively.

An attempt was made to clarify the mechanism of a chain-extending reaction of NCO-terminated prepolymers in the synthesis of segmented poly(urethane–urea) using blocked ethylenediamine (EDA) with acetone (ACE). For this purpose, an ACE/EDA mixture was allowed to react with phenyl isocyanate (PhNCO) as a model of the prepolymer. The reaction of PhNCO with the ACE/EDA mixture, which was proved to contain ketimine and imidazolidine compounds by NMR measurements, gave 1,1′-ethylenebis[3-phenylurea] (M-Ur-1) as the main product; at the same time 1,3-diphenylurea (1,3-DPU) was assumed to be formed as a side-reaction product between PhNCO and H2O, inevitably existing in the mixture as the result of condensation. From a considerable increase in the yield of M-Ur-1 upon the addition of an excess amount of H2O to the reaction system, H2O was elucidated to participate in the acceleration of the main reaction, giving M-Ur-1 as well as in the side reaction, yielding 1,3-DPU. The excess H2O added to the system might preferentially facilitate the former reaction, rather than the latter.

NCCN guidelines recommend conducting QOL assessments that display the score of a patient's quality of life, in addition tousing common assessment methods that simply diagnose the patient's medical conditions. Despite the effectiveness of these methods in determining the QOL for cancer patients, their paper answer sheets have always had a fixed format. As a result, there has been almost no progress in the efforts to digitize the questionnaires to effectively manage data, and clinicians have been required to invest inordinate amount of time and effort into collecting the EORTC assessment data in order to apply them to research. Accordingly, in this research, we used preliminary surveys to develop an application that calculates and manages data for EORTC QLQ-C30 which are the most popular QOL assessment methods. For future application, we have integrated functions to display acquired assessment data to patients using visual graphs for easy viewing and comparison, as well as a feature that allows the user to import the data from the answer sheet by simply taking a picture of it. Also, introduced a function to improve patients' motivation towards rehabilitation and encourage them to continue with rehabilitation. As a result, we succeeded in developing an application that reduces the burden of data input and analytical work on the clinician, that can present a graph that allows the cancer patient to immediately understand his or her medical condition while still showing consideration to the patient's mental state, and has a function that encourages improvement in motivation for rehabilitation.