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I need help identifying a byproduct of a Hantzsch type reaction


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I've tried using the following reactants in a Hantzsch type reaction to form a 1,4-Dihydropyridine: Propiolamide, Anisidine, Benzaldehyde.
The reaction should've given the yellow product (5-(1-aminovinyl)-1-(4-methoxyphenyl)-4-phenyl-1,4-dihydropyridine-3-carboxamide). I have since synthesized the 1,4-DHP through a different method and attached its H-NMR spectrum in DMSO below 1).
The compound that I've isolated in this synthesis was a red-yellow product that had the same mass as the 1,4-DHP. The signals in the H-NMR didn't match the 1,4-DHP. I've attached 2 spectra of this byproduct below: 2) in DMSO, 3) in Methanol.
The spectra show clearly that both aromatic rings (of the benzaldehyde and the anisidine) are in the structure. Some variation of the DHP seems to also have formed, but I can't really figure out the exact structure. There's 5 signals that dont correspond to the aromatic ring protons: signal A-E, each with an integral of 1. Two of those signals and the splitting into douplets disappears when measuring in Methanol. In DMSO one of the is at rly high ppm and two signals have unusally large coupling constants.
Does anybody have any idea what exact structure could have formed?
spectrum 1) desired 1,4-DHP in DMSO
2) byproduct in DMSO
3) byproduct in Methanol


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I just want to make sure that the structure you have shown indeed matches with the name you have provided. Actual structure of (5-(1-aminovinyl)-1-(4-methoxyphenyl)-4-phenyl-1,4-dihydropyridine-3-carboxamide) is as following:


The two hydrogens attached to the carbon-carbon double bond (highlighted in red) are expected to show a signal around 5~6 ppm. 

Edited by Ramil
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