In vitro studies on biodegradable chiral nanostructure poly(amide-imide)s containing different natural amino acids in green medium

Figures & data

Scheme 1 Preparation of amino acid containing diacid monomers, and polycondensation reactions of monomer 5 with different diacids.

Table 1. Synthesis and some physical properties of PAIs.

Monomer	Polymer	Yield (%)	μ inh (dL/g)^a	[α]D ^25 a	Color
4a	6a	95	0.45	−110.0	White
4b	6b	94	0.43	+24.5	White
4c	6c	95	0.49	−8.0	Yellow
4d	6d	96	0.45	−2.0	Yellow
^aMeasured at a concentration of 0.5 g/dL in DMF at 25 °C.

Table 2. FT-IR and ¹H-NMR characterization of PAIs.

	FT-IR peaks (KBr, cm^−1)	^1H-NMR (400 MHz, DMSO-d6 , δ, ppm)
PAI6a	3386 (m, br), 3028 (m), 2966 (m), 2932 (m), 1776 (m), 1725 (s), 1495 (m), 1455 (m), 1383 (s), 1348 (m), 727 (w), 699 (w)	0.95–1.31 (m, 12H), 2.38–2.73 (m, 8H), 3.64–3.67 (d, 4H, J = 8.4 Hz), 4.13 (s, 2H), 5.26 (s, 2H), 6.80 (s, 2H), 7.05–7.14 (m, 10H, Ar-H), 8.21 (s, 2H, Ar-H), 9.62 (s, 2H, NH)
PAI6b	3290 (m, br), 2968 (m), 2936 (m), 2870 (m), 1776 (m), 1724 (s, sh), 1591 (w), 1505 (m, br), 1455 (m), 1381 (s), 1355 (m, sh), 728 (m)	0.93–1.05 (m, 12H), 1.72 (s, 6H), 2.36–2.73 (m, 8H), 4.10 (s, 2H), 5.01–5.03 (m, 2H), 6.77 (s, 2H), 8.30 (s, 2H, Ar-H), 9.58 (s, 2H, NH)
PAI6c	3326 (w, br), 2966 (m), 2933 (m), 2875 (m), 1777 (m), 1720 (s, sh), 1590 (w), 1382 (s), 1340 (m), 722 (w), 563 (w)	0.82–1.28 (m, 24H), 1.29–1.32(m, 4H), 1.49–1.57(m, 2H), 2.33–2.67 (m, 8H), 4.08 (s, 2H), 4.69–4.72 (d, 2H, J = 8.4 Hz), 6.75 (s, 2H), 8.36 (s, 2H, Ar-H), 9.63 (s, 2H, NH)
PAI6d	3359 (w, br), 2966 (m), 2933 (m), 2874 (m), 1777 (m), 1719 (s), 1590 (w), 1383 (s), 1490 (m), 1456 (m, sh), 1187 (w), 1077 (m), 722 (w)	0.93–1.32 (m, 24H), 1.51–1.63 (m, 2H), 2.33–2.81 (m, 8H), 4.08 (s, 2H), 4.61–4.63 (d, 2H, J = 8 Hz), 6.74 (s, 2H), 8.39 (s, 2H, Ar-H), 9.60 (s, 2H, NH)

Figure 1 FT-IR (KBr) spectrum of PAI6b.

Figure 2 ¹H-NMR (400 MHz) spectrum of PAI6c in DMSO-d₆ at R.T.

Figure 3 FE-SEM micrographs of PAI6a (a), PAI6b (b), PAI6c (c), and PAI6d (d).

Figure 4 Fungal colonization of PAIs (6a–6d), monomers (4a–4d), and diamine 5.

Figure 5 Weight loss of PAIs(6a–6d), monomers (4a–4d) and diamine 5.