Carbocyclic analogs of thymine nucleosides and related 1-substituted thymines

The carbocyclic analogs of thymidine (IXf), 1-β-ribofuranosylthymine (IXg), and 1-β-3′-deoxyribofuranosyl-thymine (IXe) were synthesized by incorporating modifications into the Shaw method of synthesizing 2,4-(1H,3H)pyrimidinediones via acryloylureas. Simpler analogs of thymine nucleosides were also prepared by this method. The carbocyclic analog of thymidine displayed modest activity against Leukemia L1210 in vivo. It differs from a compound prepared previously by a Prins reaction.     

Heterodyned fifth-order two-dimensional IR spectroscopy: third-quantum states and polarization selectivity

A heterodyned fifth-order two-dimensional (2D) IR spectrum of a model coupled oscillator system, Ir(CO)(2)(C(5)H(7)O(2)), is reported. The spectrum is generated by a pulse sequence that probes the eigenstate energies up to the second overtone and combination bands, providing a more rigorous potential-energy surface of the coupled carbonyl local modes than can be obtained with third-order spectroscopy. Furthermore, the pulse sequence is designed to generate and then rephase a two-quantum coherence so that the spectrum is line narrowed and the resolution improved for inhomogeneously broadened systems. Features arising from coherence transfer processes are identified, which are more pronounced than in third-order 2D IR spectroscopy because the transition dipoles of the second overtone and combination states are not rigorously orthogonal, relaxing the polarization constraints on the signal intensity for these features. The spectrum provides a stringent test of cascading signals caused by third-order emitted fields and no cascading is observed. In the Appendix, formulas for calculating the signal intensities for resonant fifth-order spectroscopies with arbitrarily polarized pulses and transition dipoles are reported. These relationships are useful for interpreting and designing polarization conditions to enhance specific spectral features.     

Nachweis und Bestimmung organischer S?uren

Ohne Zusammenfassung     

A Study of Rectification and Liquid-Vapor Phase Equilibrium in Systems Phenol-Water-Hydroxyacetone and Phenol-Water-α-Methylstyrene

Distillation processes and the liquid-vapor phase equilibrium in the systems phenol-water-hydroxyacetone and phenol-water--methylstyrene at atmospheric pressure were studied. The direction of the distillation lines was established and the possibility of preparing pure phenol and concentrating other components, i.e., impurities, in various regions of distillation of the systems was determined.     

Carbocyclic analogs of cytosine nucleosides

The carbocyclic analogs of cytidine, 2′-deoxycytidine, and 3′-deoxycytidine were synthesized from the analogous uracil derivatives. The route consists of complete benzoylation of the uracil derivative, selective removal of a benzoyl group attached to the pyrimidine ring, conversion of the 4-oxo to a 4-chloro group with the dimethylformamide-thionyl chloride reagent, and replacement of the chloro group with an amino group in methanolic ammonia. When the total products of the deoxychlorination reaction were employed, the desired cytosine derivatives were frequently accompanied by small amounts of the corresponding N,N-dimethylcytosine derivatives, which could be removed by ion-exchange chromatography. Carbodine (VIa), the carbocyclic analog of cytidine, was obtained in 84% yield from the pure 4-chloropyrimidinone intermediate, after the latter was prepared by deoxychlorination in carbon tetrachloride. Carbodine has antileukemic, antiviral, and antibacterial activity.     

A new synthesis of 2-pyrazolin-5-ones from the condensation of C(α),N-dilithiophenylhydrazones with diethyl carbonate

C(α),N-Dilithiophenylhydrazones were prepared from phenylhydrazones in an excess of lithium diisopropylamide and condensed with diethyl carbonate followed by an acid cyclization to give 2-pyrazolin-5-ones.     

A pulse sequence for directly measuring the anharmonicities of coupled vibrations: Two-quantum two-dimensional infrared spectroscopy

We have experimentally demonstrated a pulse sequence for the acquisition of heterodyned two-dimensional infrared (2D IR) spectra that correlates the overtone and combination bands to the fundamental frequencies. The spectra are generated by Fourier transforming the time domain signal that is allowed to evolve during one- and two-quantum coherence times. In this manner, the overtone and combination bands appear along the two-quantum axis, resulting in a direct determination of the diagonal and off-diagonal anharmonicities. To demonstrate this pulse sequence, we have collected two-quantum 2D IR spectra of a ruthenium dicarbonyl complex, extracted the diagonal and off-diagonal anharmonicities, and simulated the spectra using an exciton model. Several polarization conditions are presented that suppress the diagonal or cross peaks and we have used them to improve the accuracy of the measurement.     

ON AVOIDANCE ACTIVITIES IN FISHERY ENFORCEMENT MODELS

Compliance and enforcement in fisheries are important issues from an economic point of view since management measures are useless without a certain level of enforcement. These conclusions come from the well‐established theoretical literature on compliance and enforcement problems within fisheries and a common result is that, it is efficient to set fines as high as possible and monitoring as low as possible, when fines are costless and offenders are risk neutral. However, this result is sensitive to the assumption that fishermen cannot engage in avoidance activities, e.g., activities to reduce the likelihood of being detected when noncomplying. The paper presents a model of fisheries that allows the fishermen to engage in avoidance activities. The conclusions from the model are that, under certain circumstances, fines are costly transfers to society since they not only have a direct positive effect on the level of deterrence, but also an indirect negative effect in the form of increased avoidance activities to reduce the probability of detection. The paper contributes to the literature on avoidance activities by introducing the externality from the illegal behavior as an endogenous effect on other offenders. For an externality, that has an exogenous effect on other actors, Malik shows that fines are only costly transfers for conditional deterrence (when one actor is deterred while another actor is not). For fisheries, we show that fines are also costly transfers under no deterrence (when no agents are deterred).     

Carbocyclic analogs of anhydrothymidines

The carbocyclic analog of thymidine (C-Thymidine, 2 ) was converted to the analog of 3′-(O-methanesulfonyl)-5′-O-tritylthymidine, which was cyclized in alkaline solution or with 1,5-diazabicyclo[5.4.0]undec-5-ene (DBU) to the carbocyclic analog of 5′-O-trityl-2,3′-anhydrothymidine ( 6 ). Hydrolysis of the latter compound produced the carbocyclic analog of all-cis-thymidine. C-Thymidine was also converted to the carbocyclic analog of 3′-O-acetyl-2,5′-anhydrothymidine ( 12 ) by treating the 5′-O-methanesulfonyl analog with DBU. Hydrolysis of the anhydro derivative gave back C-Thymidine. The carbocyclic analog ( 3 ) of 3′-deoxy-2′-hydroxythymidine was converted similarly to the corresponding 2,2′-anhydrothymidine ( 15 ) and 2,5′-anhydrothymidine ( 21 ) analogs. As expected, C-5′-O-trityl-2,2′-anhydrothymidine formed more readily than did the 2,3′-anhydrothymidine analog. Hydrolysis of these 2,2′- and 2,5′-anhydrothymidine analogs gave, respectively, the carbocyclic analog of all-cis-3′-deoxy-2′-hydroxythymidine and 3 .