Definition of protoporphyrin in English:

protoporphyrin

noun ˌprəʊtə(ʊ)ˈpɔːf(ɪ)rɪn

Chemistry

Any of a group of fifteen isomeric porphyrins having the formula C₃₄H₃₄N₄O₄, in which the porphin nucleus has four methyl, two vinyl, and two propionic acid substituents; especially (more fully "protoporphyrin IX") the isomer which occurs widely in living organisms, mainly as haem (in which it is bonded to an iron atom).

1920s; earliest use found in Chemical Abstracts. From proto- + porphyrin, after German Protoporphyrin.

nounˌprəʊtə(ʊ)ˈpɔːf(ɪ)rɪn

Chemistry

Any of a group of fifteen isomeric porphyrins having the formula C₃₄H₃₄N₄O₄, in which the porphin nucleus has four methyl, two vinyl, and two propionic acid substituents; especially (more fully "protoporphyrin IX") the isomer which occurs widely in living organisms, mainly as haem (in which it is bonded to an iron atom).

1920s; earliest use found in Chemical Abstracts. From proto- + porphyrin, after German Protoporphyrin.

词汇	protoporphyrin
释义	Definition of protoporphyrin in English: protoporphyrin noun ˌprəʊtə(ʊ)ˈpɔːf(ɪ)rɪn Chemistry Any of a group of fifteen isomeric porphyrins having the formula C₃₄H₃₄N₄O₄, in which the porphin nucleus has four methyl, two vinyl, and two propionic acid substituents; especially (more fully "protoporphyrin IX") the isomer which occurs widely in living organisms, mainly as haem (in which it is bonded to an iron atom). Origin 1920s; earliest use found in Chemical Abstracts. From proto- + porphyrin, after German Protoporphyrin. Definition of protoporphyrin in US English: protoporphyrin nounˌprəʊtə(ʊ)ˈpɔːf(ɪ)rɪn Chemistry Any of a group of fifteen isomeric porphyrins having the formula C₃₄H₃₄N₄O₄, in which the porphin nucleus has four methyl, two vinyl, and two propionic acid substituents; especially (more fully "protoporphyrin IX") the isomer which occurs widely in living organisms, mainly as haem (in which it is bonded to an iron atom). Origin 1920s; earliest use found in Chemical Abstracts. From proto- + porphyrin, after German Protoporphyrin.
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