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  2. Pyrrole - Wikipedia

    en.wikipedia.org/wiki/Pyrrole

    Pyrrole has a nutty odor. Pyrrole is a 5-membered aromatic heterocycle, like furan and thiophene. Unlike furan and thiophene, it has a dipole in which the positive end lies on the side of the heteroatom, with a dipole moment of 1.58 D. In CDCl 3, it has chemical shifts at 6.68 (H2, H5) and 6.22 (H3, H4).

  3. Knorr pyrrole synthesis - Wikipedia

    en.wikipedia.org/wiki/Knorr_pyrrole_synthesis

    The Knorr pyrrole synthesis is a widely used chemical reaction that synthesizes substituted pyrroles (3). [ 1 ] [ 2 ] [ 3 ] The method involves the reaction of an α- amino - ketone (1) and a compound containing an electron-withdrawing group (e.g. an ester as shown) α to a carbonyl group (2) .

  4. Hantzsch pyrrole synthesis - Wikipedia

    en.wikipedia.org/wiki/Hantzsch_pyrrole_synthesis

    [1] [2] Pyrroles are found in a variety of natural products with biological activity, so the synthesis of substituted pyrroles has important applications in medicinal chemistry. [3] [4] Alternative methods for synthesizing pyrroles exist, such as the Knorr Pyrrole Synthesis and Paal-Knorr Synthesis. The Hantzsch pyrrole synthesis

  5. Odor detection threshold - Wikipedia

    en.wikipedia.org/wiki/Odor_detection_threshold

    The odour activity value is the concentration divided by the threshold. The flavor impact is the value the rate of change in perception with concentration. The flavor contribution of an aroma component in a mixture to the total profile can be calculated from the total odor units and the number contributed by that aroma chemical.

  6. Polypyrrole - Wikipedia

    en.wikipedia.org/wiki/Polypyrrole

    Polypyrrole Pyrrole can be polymerised electrochemically. [1] Polypyrrole (PPy) is an organic polymer obtained by oxidative polymerization of pyrrole. It is a solid with the formula H(C 4 H 2 NH) n H. It is an intrinsically conducting polymer, used in electronics, optical, biological and medical fields. [2] [3]

  7. Protein pKa calculations - Wikipedia

    en.wikipedia.org/wiki/Protein_pKa_calculations

    See Amino acid for the pK a values of all amino acid side chains inferred in such a way. There are also numerous experimental studies that have yielded such values, for example by use of NMR spectroscopy. The table below lists the model pK a values that are often used in a protein pK a calculation, and contains a third column based on protein ...

  8. Ehrlich's reagent - Wikipedia

    en.wikipedia.org/wiki/Ehrlich's_reagent

    It gives a negative test-result for 25I-NBOMe and many other non-indole-related psychoactives. The reagent will also give a positive result for opium, because of the presence of tryptophan in natural opium. [3] Pyridoxine, present in vitamin supplements, can give positive results to the Ehrlich test, showing a pink colour change. [4]

  9. meso-Octamethylporphyrinogen - Wikipedia

    en.wikipedia.org/wiki/Meso-Octamethylporphyrinogen

    meso-Octamethylporphyrinogen, usually referred to simply as octamethylporphyrinogen, is an organic compound with the formula (Me 2 C-C 4 H 2 NH) 4 (Me = CH 3.It is one of the simplest porphyrinogens, a family of compounds that occur as intermediates in the biosynthesis of hemes and chlorophylls.