Electron density and electrostatic properties of two peptide molecules: tyrosyl-glycyl-glycine ­monohydrate and glycyl-aspartic acid dihydrate

The electron density and electrostatic properties of Tyr-Gly-Gly and Gly-Asp molecules have been determined from high-resolution X-ray diffraction data at 123 K. Topological properties of the charge distribution are discussed and compared with those derived from other experimental studies on peptide molecules, and the characteristics of the (3,−1) critical points of the C=O, C—N, C—C bonds are analysed. Crystal data for Tyr-Gly-Gly: C₁₃H₁₇N₃O₅·H₂O, M_r = 313, orthorhombic, P2₁2₁2₁, Z = 4, T = 123 ± 2 K; lattice parameters: a = 7.984 (2), b = 9.535 (3), c = 18.352 (5) Å, V = 1397.1 (6) ų, D_x = 1.49 g cm⁻³, μ = 1.2 cm⁻¹ for λ_Mo = 0.7107 Å. Crystal data for Gly-Asp: C₆H₁₀N₂O₅·2H₂O, M_r = 212, orthorhombic, P2₁2₁2₁, Z = 4, T = 123 ± 2 K; lattice parameters: a = 9.659 (1), b = 9.672 (1), c = 10.739 (1) Å, V = 1003.3 (4) ų, D_x = 1.40 g cm⁻³, μ = 1.3 cm⁻¹ for λ_Mo = 0.7107 Å.

Computing details

(YGG)

Crystal data

C13H17N3O5·H2O	c = 18.352 (5) Å
Mr = 313	V = 1397.1 (6) Å^3
Orthorhombic, P212121	Z = 4
a = 7.984 (2) Å	Dx = 1.49 Mg m^−3
b = 9.535 (3) Å	Mo Kα radiation, λ = 0.7107 Å

Data collection

h = →	l = →
k = →

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.29679 (6)	0.38515 (6)	−0.05665 (3)	0.015 (1)
O2	0.14819 (7)	0.49680 (6)	0.14781 (2)	0.014 (1)
O31	0.21920 (6)	0.99642 (5)	0.11764 (3)	0.014 (1)
O32	−0.00356 (7)	0.85722 (5)	0.13385 (3)	0.015 (1)
OH1	0.22461 (7)	−0.22641 (5)	−0.08568 (3)	0.019 (1)
O6	0.07754 (7)	0.22615 (5)	0.18999 (3)	0.016 (1)
N1	0.30502 (7)	0.43883 (6)	−0.19877 (3)	0.012 (1)
N2	0.02553 (7)	0.44865 (6)	−0.04149 (3)	0.011 (1)
N3	0.15617 (8)	0.64654 (6)	0.05190 (3)	0.013 (1)
C1	0.16215 (9)	0.42107 (7)	−0.08231 (3)	0.010 (1)
C1A	0.13657 (9)	0.43357 (7)	−0.16456 (3)	0.011 (1)
C1B	0.03320 (9)	0.30932 (7)	−0.19391 (4)	0.012 (1)
C2	0.11734 (8)	0.52464 (7)	0.08310 (4)	0.011 (1)
C2A	0.02899 (9)	0.41640 (7)	0.03566 (3)	0.012 (1)
C3A	0.24986 (9)	0.75644 (7)	0.08749 (4)	0.014 (1)
C3	0.14502 (9)	0.88070 (7)	0.11413 (3)	0.011 (1)
C1G	0.08635 (9)	0.16721 (7)	−0.16566 (4)	0.011 (1)
C1E1	0.25135 (9)	−0.04652 (7)	−0.17721 (4)	0.013 (1)
C1D1	0.20376 (9)	0.08535 (7)	−0.20273 (3)	0.013 (1)
C1Z	0.18290 (9)	−0.09706 (7)	−0.11268 (4)	0.013 (1)
C1D2	0.01886 (9)	0.11386 (7)	−0.10092 (4)	0.013 (1)
C1E2	0.06705 (9)	−0.01667 (8)	−0.07405 (4)	0.013 (1)
H1A	0.07006	0.52955	−0.17707	0.014 (4)
H1B1	0.04423	0.31095	−0.25288	0.016 (4)
H1B2	−0.09621	0.32677	−0.17925	0.016 (4)
H2A1	0.09148	0.31784	0.04781	0.016 (4)
H2A2	−0.09968	0.40770	0.05397	0.016 (4)
H3A1	0.30966	0.71877	0.13672	0.018 (4)
H3A2	0.34161	0.79795	0.04932	0.018 (4)
HN11	0.38315	0.51581	−0.17837	0.016 (4)
HN12	0.37513	0.34997	−0.18861	0.016 (4)
HN13	0.29803	0.44493	−0.25472	0.016 (4)
HN2	−0.08852	0.46827	−0.06568	0.016 (4)
HN3	0.13114	0.66368	−0.00231	0.016 (4)
H1D1	0.25965	0.12356	−0.25196	0.017 (4)
H1E1	0.34288	−0.10783	−0.20536	0.017 (4)
H1D2	−0.06714	0.17524	−0.06934	0.017 (4)
H1E2	0.02153	−0.05945	−0.02374	0.017 (4)
HO5	0.32902	−0.26132	−0.10473	0.015 (4)
HW1	0.12995	0.15704	0.15916	0.021 (5)
HW2	0.10614	0.31906	0.17356	0.021 (5)

Geometric parameters (Å, º)

N1—C1A	1.4851 (9)	C2A—C2	1.5233 (9)
C1A—C1B	1.5409 (9)	C2—O2	1.2416 (8)
C1B—C1G	1.5115 (10)	C2—N3	1.3322 (9)
C1G—C1D1	1.3967 (10)	N3—C3A	1.4436 (9)
C1G—C1D2	1.4002 (9)	C3A—C3	1.5307 (10)
C1D1—C1E1	1.3945 (10)	C3—O31	1.2539 (9)
C1D2—C1E2	1.3929 (10)	C3—O32	1.2603 (9)
C1E1—C1Z	1.3904 (10)	O6—HW1	0.9640 (5)
C1E2—C1Z	1.3949 (10)	O6—HW2	0.9632 (5)
C1Z—OH1	1.3701 (9)	OH1—HO5	0.9633 (6)
C1A—C1	1.5280 (9)	N1—HN11	1.0334 (6)
C1—O1	1.2225 (9)	N1—HN12	1.0324 (6)
C1—N2	1.3491 (9)	N1—HN13	1.0300 (6)
N2—C2A	1.4492 (8)
N1—C1A—C1	107.41 (5)	C3A—C3—O32	117.97 (6)
N1—C1A—C1B	111.30 (6)	O31—C3—O32	125.88 (7)
C1A—C1—O1	121.33 (6)	C1A—C1B—C1G	114.77 (6)
C1A—C1—N2	115.17 (6)	C1B—C1G—C1D1	121.49 (6)
O1—C1—N2	123.48 (6)	C1B—C1G—C1D2	120.57 (6)
C1—N2—C2A	119.06 (6)	C1G—C1D1—C1E1	121.54 (6)
C1—C1A—C1B	110.91 (6)	C1G—C1D2—C1E2	121.25 (7)
N2—C2A—C2	115.05 (6)	C1D1—C1E1—C1Z	119.44 (7)
C2A—C2—O2	119.58 (6)	C1D2—C1E2—C1Z	119.62 (7)
C2A—C2—N3	116.95 (6)	C1E1—C1Z—C1E2	120.20 (7)
O2—C2—N3	123.46 (7)	C1E1—C1Z—OH1	121.63 (6)
C2—N3—C3A	124.02 (6)	C1E2—C1Z—OH1	118.16 (6)
N3—C3A—C3	115.02 (6)	HW1—O6—HW2	110.00 (5)
C3A—C3—O31	116.05 (6)

Hydrogen-bond geometry (Å, º)

D—H···A	H···A	D···A	D—H···A
O6—HW2···O2	1.79	2.7525 (7)	176
N1—HN13···O2^i	1.92	2.9057 (7)	159
N2—HN2···O31^ii	1.84	2.8652 (8)	174
O6—HW1···O31^iii	1.85	2.8000 (7)	167
OH1—HO5···O32^iv	1.70	2.6547 (9)	168
N1—HN11···O32^v	1.72	2.7453 (9)	172
N3—HN3···OH1^vi	2.00	2.8534 (8)	139
N1—HN12···O6^iv	1.77	2.6898 (9)	146

Symmetry codes: (i) −x+1/2, −y+1, z−1/2; (ii) x−1/2, −y+3/2, −z; (iii) x, y−1, z; (iv) x+1/2, −y+1/2, −z; (v) x+1/2, −y+3/2, −z; (vi) x, y+1, z.

(GD)

Crystal data

C6H10N2O5·2(H2O)	c = 10.739 (1) Å
Mr = 212	V = 1003.3 (4) Å^3
Orthorhombic, P212121	Z = 4
a = 9.659 (1) Å	Dx = 1.40 Mg m^−3
b = 9.672 (1) Å	Mo Kα radiation, λ = 0.7107 Å

Data collection

h = →	l = →
k = →

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O21	−0.78621 (4)	−0.27464 (4)	−0.22757 (4)	0.015 (1)
O22	−0.94748 (4)	−0.14220 (4)	−0.31605 (4)	0.017 (1)
C2	−0.82426 (5)	−0.16995 (5)	−0.28803 (5)	0.012 (1)
C2A	−0.71303 (5)	−0.06645 (5)	−0.32942 (5)	0.013 (1)
N2	−0.57674 (4)	−0.11497 (4)	−0.29271 (5)	0.014 (1)
C1	−0.48454 (5)	−0.03277 (5)	−0.23657 (4)	0.012 (1)
O1	−0.50751 (4)	0.08792 (4)	−0.20603 (4)	0.018 (1)
C1A	−0.34498 (5)	−0.10086 (5)	−0.21273 (5)	0.015 (1)
N1	−0.26556 (5)	−0.01730 (5)	−0.12333 (5)	0.015 (1)
C2B	−0.71587 (6)	−0.03553 (5)	−0.46976 (5)	0.016 (1)
C2G	−0.67069 (5)	−0.16118 (5)	−0.54215 (5)	0.014 (1)
O2D1	−0.71240 (5)	−0.27664 (4)	−0.51789 (4)	0.019 (1)
O2D2	−0.58222 (5)	−0.13440 (4)	−0.63233 (5)	0.022 (1)
OW1	−0.95007 (4)	−0.41590 (4)	−0.06995 (4)	0.018 (1)
OW2	−0.39866 (5)	0.19248 (5)	−0.48429 (5)	0.024 (1)
H2A	−0.74147 (3)	0.02974 (3)	−0.28281 (3)	0.016 (6)
HN2	−0.54291 (3)	−0.21517 (3)	−0.30427 (3)	0.019 (6)
H1A1	−0.36615 (3)	−0.20362 (3)	−0.17549 (3)	0.020 (6)
H1A2	−0.29585 (3)	−0.10799 (3)	−0.30204 (3)	0.020 (7)
HN11	−0.32591 (3)	−0.00694 (3)	−0.04364 (3)	0.020 (7)
HN12	−0.17890 (3)	−0.07177 (3)	−0.09329 (3)	0.020 (6)
HN13	−0.24809 (3)	0.07590 (3)	−0.16559 (3)	0.020 (6)
H2B1	−0.82348 (3)	−0.02143 (3)	−0.49598 (3)	0.021 (7)
H2B2	−0.64005 (3)	0.04544 (3)	−0.48652 (3)	0.021 (6)
HD22	−0.54140 (4)	−0.21932 (4)	−0.66273 (3)	0.030 (8)
HW11	−0.89563 (3)	−0.36954 (3)	−0.13191 (3)	0.024 (7)
HW12	−1.00414 (3)	−0.48600 (3)	−0.11074 (3)	0.024 (7)
HW21	−0.34677 (4)	0.21581 (3)	−0.41107 (3)	0.031 (8)
HW22	−0.44338 (3)	0.27255 (4)	−0.51934 (3)	0.031 (8)

Geometric parameters (Å, º)

N1—C1A	1.4705 (7)	C2B—C2G	1.5069 (7)
C1A—C1	1.5219 (7)	C2G—O2D1	1.2159 (6)
C1—O1	1.2327 (6)	C2G—O2D2	1.3168 (7)
C1—N2	1.3373 (7)	O2D2—HD22	0.9604 (4)
N2—C2A	1.4520 (7)	OW1—HW11	0.9647 (4)
C2A—C2	1.5346 (7)	OW1—HW12	0.9612 (4)
C2—O21	1.2576 (6)	OW2—HW21	0.9625 (5)
C2—O22	1.2567 (6)	OW2—HW22	0.9713 (5)
C2A—C2B	1.5367 (7)
N1—C1A—C1	109.53 (4)	O21—C2—O22	124.91 (5)
C1A—C1—O1	121.61 (5)	C2A—C2B—C2G	110.12 (4)
C1A—C1—N2	114.13 (4)	C2B—C2G—O2D1	122.27 (5)
O1—C1—N2	124.26 (5)	C2B—C2G—O2D2	114.15 (4)
C1—N2—C2A	122.25 (4)	O2D1—C2G—O2D2	123.58 (5)
N2—C2A—C2	110.17 (4)	C2G—O2D2—HD22	110.11 (4)
N2—C2A—C2B	110.23 (4)	HW11—OW1—HW12	108.10 (4)
C2A—C2—O21	118.07 (4)	HW21—OW2—HW22	111.43 (5)
C2A—C2—O22	117.02 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	H···A	D···A	D—H···A
OW1—HW11···O21	1.73	2.6905 (6)	172
N1—HN13···O21^i	1.86	2.8852 (7)	170
OD22—HD22···O22^ii	1.64	2.5826 (6)	167
OW1—HW12···O22^iii	1.77	2.6960 (6)	162
N2—HN2···O1^iv	1.97	2.9875 (6)	167
OW2—HW22···OW1^v	1.81	2.7666 (7)	172
N1—HN11···OW1^vi	1.87	2.8110 (7)	150
N1—HN12···OW2^vii	1.83	2.7595 (7)	147
OW2—HW21···O21^i	1.96	2.9100 (7)	166

Symmetry codes: (i) −x−1, y+1/2, −z−1/2; (ii) x+1/2, −y−1/2, −z−1; (iii) −x+2, y−1/2, −z−1/2; (iv) −x−1, y−1/2, −z−1/2; (v) −x+5/2, −y, z−1/2; (vi) x+1/2, −y−1/2, −z; (vii) −x−1/2, −y, z+1/2.