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Pyrrole is an extremely weak base for an amine, with a conjugate acid pK a of −3.8. The most thermodynamically stable pyrrolium cation (C 4 H 6 N +) is formed by protonation at the 2 position. Substitution of pyrrole with alkyl substituents provides a more basic molecule—for example, tetramethylpyrrole has a conjugate acid pK a of +3.7.
Skeletal formula of retronecine, a pyrrolizidine alkaloid found in the common groundsel (Senecio vulgaris) and comfrey (Symphytum spp.) . Pyrrolizidine alkaloids (PAs), sometimes referred to as necine bases, are a group of naturally occurring alkaloids based on the structure of pyrrolizidine.
Pyrrolidine, also known as tetrahydropyrrole, is an organic compound with the molecular formula (CH 2) 4 NH. It is a cyclic secondary amine , also classified as a saturated heterocycle . It is a colourless liquid that is miscible with water and most organic solvents.
The "side chain" from the α carbon connects to the nitrogen forming a pyrrolidine loop, classifying it as a aliphatic amino acid. It is non-essential in humans, meaning the body can synthesize it from the non-essential amino acid L-glutamate. It is encoded by all the codons starting with CC (CCU, CCC, CCA, and CCG).
Alkaloids with partial pyrrolidine structure are usually sub-categorized based on their occurrence and biogenetic origin. Hygrin and cuscohygrin were isolated from the leaves of the coca shrub, [2] while (-)-codonopsinine was isolated from the woodland vine tiger bell.
Nutrition facts (3 oz., canned in water): 110 cal, 2.5g total fat, 35mg cholesterol 320mg sodium, 0g carb, 0g fiber, 20g protein RELATED: 10 Healthy Fish to Eat If You Want to Crush Your Weight ...
A library of substituted pyrrole analogs can be quickly produced by using continuous flow chemistry (reaction times of around 8 min.). [10] The advantage of using this method, as opposed to the in-flask synthesis, is that this one does not require the work-up and purification of several intermediates, and could therefore lead to a higher ...
The starting material was an N-substituted pyrrole derivative, which was heated to convert it by a [1,5] sigmatropic shift to the isomer with a carbon bond between the pyrrole and pyridine rings, followed by methylation and selective reduction of the pyrrole ring using tin and hydrochloric acid.