prov:value
| - wherein A represents ???R4???X, wherein R4 represents an alkyl group having from about 1 to about 10 carbons, or from about 1 to about 8 carbons, such as methyl, ethyl, propyl, and the like, X represents ???NH2 or ???NHR5NH2 with R5 being the same as R4 above; R1 and R2 are the same or different and each is an alkyl having from about 1 to about 25 carbons, such as methyl, ethyl, propyl, butyl, and
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