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    Wondering if anyone can help me draw this tripeptide...
    http://www.ocr.org.uk/download/asses..._unit_f324.pdf

    It's on page 5 on the PDF and is question ci)

    Thanks!
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    It's just an addition-elimination reaction to form two amide bonds:

    R-COOH + NH2-R ---> R-CONH-R + water

    that help?
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    H2N - C - CO - NH - C - CO - N - C - COOH

    cba to draw the R groups, or the H atom above the R. basically they're amide bonds so remove the OH group of the carboxylic acid and a H from the amine group. you keep C=O and then have the NH. you'll also have 2 H2O molecules formed from the condensation too, as by-products.

    quote me if this explanation isn't quite clear enough and you want more help
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    (Original post by EierVonSatan)
    It's just an addition-elimination reaction to form two amide bonds:

    R-COOH + NH2-R ---> R-CONH2-R + water

    that help?
    It's basically the last amino giving me the problem, the proline because it doesn't have NH2
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    (Original post by EierVonSatan)
    It's just an addition-elimination reaction to form two amide bonds:

    R-COOH + NH2-R ---> R-CONH2-R + water

    that help?
    R-CONH-R *
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    (Original post by wilsea05)
    H2N - C - CO - NH - C - CO - N - C - COOH

    cba to draw the R groups, or the H atom above the R. basically they're amide bonds so remove the OH group of the carboxylic acid and a H from the amine group. you keep C=O and then have the NH. you'll also have 2 H2O molecules formed from the condensation too, as by-products.

    quote me if this explanation isn't quite clear enough and you want more help
    Will the CO - N count as a peptide bond? Thought it had to be CO NH...
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    (Original post by tripodd)
    It's basically the last amino giving me the problem, the proline because it doesn't have NH2
    i've not actually done this section of A2 chemistry yet. however i'd assume that it keeps the ring and loses the only H that is there. or the ring is lost and it becomes an aliphatic side chain. 50/50 chance?

    EDIT: i thought this was F325 for some reason. i have in fact done this. i'd assume it kept the ring and lost the H, so yeh R-CON-R
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    (Original post by wilsea05)
    i've not actually done this section of A2 chemistry yet. however i'd assume that it keeps the ring and loses the only H that is there. or the ring is lost and it becomes an aliphatic side chain. 50/50 chance?
    Wouldnt think it counts as a CO N... cause that's not the peptide bond - anyone know what would happen?
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    i don't think the H on the N is compulsory for it to qualify as a peptide bond
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    (Original post by wilsea05)
    R-CONH-R *
    Yup, my bad - edited.

    OP: It doesn't need the hydrogen on the nitrogen for it to be an amide bond and the ring remains in the tripeptide
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    (Original post by EierVonSatan)
    Yup, my bad - edited.

    OP: It doesn't need the hydrogen on the nitrogen for it to be an amide bond and the ring remains in the tripeptide
    Thanks for the confirmation
    Thanks wilsea05 for the help too

    much appreciated
 
 
 
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