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ADDENDA AND ERRATA

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6-tert-Butyl-4-[(4-hy­dr­oxy­methyl-2H-1,2,3-triazol-2-yl)meth­yl]-2H-chromen-2-one

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aDepartment of Studies in Physics, Manasagangotri, University of Mysore, Mysore 570 006, India, and bDepartment of Chemistry, Central College Campus, Bangalore University, Bangalore 560 001, India
*Correspondence e-mail: mahendra@physics.uni-mysore.ac.in

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 9 October 2016; accepted 12 October 2016; online 28 October 2016)

In the title compound, C17H19N3O3, the triazole ring and the chromene ring system [maximum deviation = 0.018 (2) Å for the O atom] bridged via a methyl­ene C atom, are inclined to one another by 73.2 (1)°. In the crystal, mol­ecules are linked by O—H⋯N hydrogen bonds, forming zigzag chains along [001]. The chains are linked by C—H⋯O hydrogen bonds, forming layers parallel to (010), and these layers are linked by C—H⋯π and ππ inter­actions [intercentroid distance = 3.557 (1) Å], forming a three-dimensional newwork. The hy­droxy­methyl group at the 4-position of the triazole ring is disordered over two sets of sites, with a refined occupancy ratio of 0.418 (11):0.584 (11).

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Chromones are a group of natural and synthetic oxygen heterocyclic compounds having a high degree of chemical diversity that is frequently linked to a broad array of biological activities (Gaspar et al., 2015[Gaspar, A., Milhazes, N., Santana, L., Uriarte, E., Borges, F. & Matos, M. J. (2015). Curr. Top. Med. Chem. 15, 432-445.]). Coumarins and their derivatives have wide applications in a number of diverse areas. They are used in the pharmaceutical industry as precursor reagents in the synthesis of a number of synthetic anti­coagulant pharmaceuticals (Bairagi et al., 2012[Bairagi, S. H., Salaskar, P. P., Loke, S. D., Surve, N. N., Tandel, D. V. & Dusara, M. D. (2012). Int. J. Pharm. Res. 4, 16-19.]), the most notable being warfarin (Holbrook et al., 2005[Holbrook, A. M., Pereira, J. A., Labiris, R., McDonald, H., Douketis, J. D., Crowther, M. & Wells, P. S. (2005). Arch. Intern. Med. 165, 1095-1106.]). Modified coumarins are a type of vitamin K antagonist (Marongiu & Barcellona, 2015[Marongiu, F. & Barcellona, D. (2015). Bioactive Nutraceuticals and Dietary Supplements in Neurological and Brain Disease, edited by R. R. Watson & V. R. Preedy, pp. 395-398. New York: Academic Press.]). Coumarins are of great inter­est due to their biological properties (Lacy & O'Kennedy, 2004[Lacy, A. & O'Kennedy, R. (2004). Curr. Pharm. Des. 10, 3797-3811.]). In particular, their physiological, bacteriostatic and anti-tumour activity (Mustafa et al., 2011[Mustafa, M. S., El-Abadelah, M. M., Zihlif, M. A., Naffa, R. G. & Mubarak, M. S. (2011). Molecules, 16, 4305-4317.]) makes these compounds attractive for further backbone derivatization and screening for their therapeutic properties. 2H-chromen-2-ones exhibit extensive natural occurrence and biocompatibility, and have been found to exhibit variety of biological activities (Naik et al., 2012[Naik, R. J., Kulkarni, M. V., Pai, K. S. R. & Nayak, P. G. (2012). Chem. Biol. Drug Des. 80, 516-523.]).

In the mol­ecular structure of the title compound (Fig. 1[link]), the chromene unit (O16/C9—C15/C17/C18), as expected, is almost planar, with a maximum deviation of 0.018 (2) Å for the ring atom O16. The carbonyl O atom, O19, is displaced from the chromene mean plane by 0.059 (2) Å. The triazole (N1/N4/N5/C2/C3) and the chromene (O16/C9–C15/C17/C18) rings, bridged via a methyl­ene C atom, C8, are inclined to one another by 73.2 (1)°. The intra-ring bond conformation between chromene and triazole moieties are also characterized by torsion angles of −72.6 (2)° (C9—C8—N1—N5) and 178.24 (18)° (C20—C12—C11—C10). The hy­droxy­methyl O atom is not coplanar with the triazole ring, as indicated by torsion angle C2—C3—C6B—O7B = −58 (2)°. One methyl unit of the tert-butyl group is almost coplanar with the chromene ring as suggested by the torsion angle C11—C12—C20—C23 = 5.2 (3)°, while the other two methyl groups are above and below the ring plane, with torsion angles C13—C12—C20—C21 and C13—C12—C20—C22, being 64.9 (2) and −54.7 (3)°, respectively.

[Figure 1]
Figure 1
A view of the mol­ecular structure of the title compound, with the atom labelling. Displacement ellipsoids are drawn at the 50% probability (atoms C6A/O7A and C6B/O7B concern the disordered hy­droxy­methyl group).

In the crystal, mol­ecules are are linked by an O—H⋯N hydrogen bond, forming chains along the c-axis direction (Table 1[link]). The chains are linked by C—H⋯O hydrogen bonds, forming layers parallel to the ac plane (Table 1[link] and Fig. 2[link]). Finally, the layers are linked by C—H⋯π and ππ inter­actions, forming a three-dimensional network (Table 1[link] and Fig. 2[link]). The ππ inter­actions involve Cg1⋯Cg2i = Cg2⋯Cg1ii = 3.557 (1) Å [the two rings are inclined to one another by 14.95 (11)°, and the inter­planar distances and slippages are 3.463 (1) and 1.545 Å, and 3.204 (1) and 0.812 Å, respectively; Cg1 and Cg2 are the centroids of rings N1/N4/N5/C2/C3 and O16/C9/C10/C15/C17/C18; symmetry codes: (i) −x + 1, −y + 1, z − [{1\over 2}] and (ii) −x + 1, −y + 1, z + [{1\over 2}]].

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 is the centroid of the C10–C15 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
O7B—H7B⋯N4i 0.82 2.49 3.198 (7) 146
C2—H2⋯O19ii 0.93 2.54 3.365 (3) 147
C23—H23B⋯O19iii 0.96 2.59 3.421 (3) 146
C22—H22BCg3iv 0.96 2.99 3.818 (3) 145
Symmetry codes: (i) [-x+2, -y+1, z-{\script{1\over 2}}]; (ii) x, y, z-1; (iii) x-1, y, z-1; (iv) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z].
[Figure 2]
Figure 2
A view along the c axis of the crystal packing of the title compound. The hydrogen bonds are shown as dashed lines and the C—H⋯π inter­actions as black lines (see Table 1[link]), and examples of the ππ interactions as thick orange lines. For clarity, only the H atoms involved in these inter­molecular inter­actions have been included.

Synthesis and crystallization

A mixture of propargyl alcohol (1.9 mmol), sodium azide (0.14 g, 2.0 mmol), copper(I) iodide (10 mol%) and tri­ethyl­amine (0.19 g, 1.9 mmol) in 20 ml of acetone was taken in a round-bottom flask and stirred for 1 h. To this mixture, 4-bromo­methyl­coumarin (1.9 mmol) was added and the stirring continued for 8 h (the reaction was monitored by TLC). After the completion of the reaction, the catalyst was filtered through celite and the product was extracted with ether (3.10 ml). The solvent was removed under vacuum. The crude product was dried and recrystallized from ethyl acetate solution to give colourless block-like crystals of the title compound (yield 90%, m.p. 473–475 K). IR (KBr, cm−1): 1715 (lactone C=O), 3221 (OH). 1H NMR (400 MHz, CDC13): δ 1.28 (s, 9H, 3-CH3 of tert-butyl group), 1.70 (s, 1H, OH), 4.84 (s, 2H, –CH2O–), 5.77 (s, 2H, –CH2N–), 6.06 (s, 1H, C3—H), 7.31 (d, 1H, C7—H, J1,2 = 12 Hz), 7.57(s, 1H, C5—H), 7.61(d, 1H, C8—H, J1,2 = 8.8 Hz), 7.73 (s, 1H, Tr—H) p.p.m. 13C NMR (100 MHz, DMSO-d6): δ 31.0 (3C), 34.5, 49.2, 54.9, 113.7, 116.3, 116.4, 121.0, 123.7, 129.8, 147.0, 148.6, 150.4, 151.1, 159.5 p.p.m.. Analysis for C17H19N3O3. Calculated: C, 65.16; H, 6.11; N, 13.41%. Found: C, 65.12; H, 6.07; N, 13.39%.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. The hy­droxy­methyl group at the 4-position of the triazole ring is disordered over two sets of sites, with a refined occupancy ratio of 0.418 (11):0.584 (11) for atoms C6A:C6B and O7A:O7B. The structure was refined as an inversion twin; Flack parameter = 0.2 (5).

Table 2
Experimental details

Crystal data
Chemical formula C17H19N3O3
Mr 313.35
Crystal system, space group Orthorhombic, Pna21
Temperature (K) 293
a, b, c (Å) 8.9099 (12), 24.550 (3), 7.2359 (11)
V3) 1582.7 (4)
Z 4
Radiation type Cu Kα
μ (mm−1) 0.75
Crystal size (mm) 0.32 × 0.22 × 0.12
 
Data collection
Diffractometer Bruker X8 Proteum
No. of measured, independent and observed [I > 2σ(I)] reflections 5136, 1581, 1565
Rint 0.022
(sin θ/λ)max−1) 0.585
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.080, 1.07
No. of reflections 1581
No. of parameters 227
No. of restraints 38
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.10, −0.11
Computer programs: APEX2 and SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS2016 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2016 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]).

Structural data


Computing details top

6-tert-Butyl-4-[(4-hydroxymethyl-2H-1,2,3-triazol-2-yl)methyl]-2H-chromen-2-one top
Crystal data top
C17H19N3O3Dx = 1.315 Mg m3
Mr = 313.35Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, Pna21Cell parameters from 1581 reflections
a = 8.9099 (12) Åθ = 7.2–64.4°
b = 24.550 (3) ŵ = 0.75 mm1
c = 7.2359 (11) ÅT = 293 K
V = 1582.7 (4) Å3Block, colourless
Z = 40.32 × 0.22 × 0.12 mm
F(000) = 664
Data collection top
Bruker X8 Proteum
diffractometer
1565 reflections with I > 2σ(I)
Radiation source: Bruker MicroStar microfocus rotating anodeRint = 0.022
Helios multilayer optics monochromatorθmax = 64.4°, θmin = 7.2°
Detector resolution: 18.4 pixels mm-1h = 109
φ and ω scansk = 2827
5136 measured reflectionsl = 38
1581 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.030H-atom parameters constrained
wR(F2) = 0.080 w = 1/[σ2(Fo2) + (0.0492P)2 + 0.1878P]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max < 0.001
1581 reflectionsΔρmax = 0.10 e Å3
227 parametersΔρmin = 0.11 e Å3
38 restraintsAbsolute structure: Refined as an inversion twin
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.2 (5)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refined as a 2-component inversion twin.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
C120.1311 (2)0.32195 (7)0.4515 (3)0.0390 (4)
N10.60931 (17)0.47866 (6)0.3641 (3)0.0440 (4)
C110.2465 (2)0.35946 (7)0.4284 (3)0.0362 (4)
H110.2467060.3813020.3233340.043*
O160.47177 (19)0.33551 (6)0.8472 (3)0.0573 (4)
C130.1364 (2)0.28959 (8)0.6120 (3)0.0498 (5)
H130.0606680.2641680.6317430.060*
C150.3613 (2)0.33239 (8)0.7134 (3)0.0431 (5)
O190.6737 (2)0.37446 (8)0.9624 (3)0.0858 (7)
C90.4845 (2)0.40488 (8)0.5398 (3)0.0399 (5)
N40.7328 (2)0.54936 (8)0.4439 (3)0.0576 (5)
C100.3626 (2)0.36557 (7)0.5575 (3)0.0359 (4)
C20.7321 (2)0.47844 (8)0.2567 (3)0.0438 (5)
H20.7579060.4531110.1665580.053*
N50.6080 (2)0.52202 (8)0.4770 (3)0.0578 (6)
C170.5846 (3)0.37326 (9)0.8355 (4)0.0564 (6)
C80.4850 (2)0.44007 (9)0.3695 (4)0.0472 (5)
H8A0.4901870.4168410.2612300.057*
H8B0.3912250.4600960.3636930.057*
C180.5886 (2)0.40772 (9)0.6742 (4)0.0497 (5)
H180.6660890.4328630.6626080.060*
C200.0017 (2)0.31619 (8)0.3138 (4)0.0442 (5)
C230.0228 (3)0.35213 (11)0.1440 (4)0.0645 (7)
H23A0.0233990.3897030.1807800.097*
H23B0.0581500.3459810.0589160.097*
H23C0.1163340.3433490.0853320.097*
C210.1441 (2)0.33404 (11)0.4108 (5)0.0676 (7)
H21A0.1352540.3713640.4488020.101*
H21B0.1608970.3114890.5171780.101*
H21C0.2268730.3303790.3268340.101*
C140.2491 (3)0.29416 (9)0.7405 (3)0.0531 (5)
H140.2501150.2718570.8443580.064*
C6A0.957 (3)0.5456 (15)0.238 (6)0.0620 (7)0.418 (11)
H6A10.9817760.5280380.1216980.074*0.418 (11)
H6A20.9475950.5843960.2157570.074*0.418 (11)
O7A1.0709 (6)0.5357 (3)0.3685 (13)0.076 (3)0.418 (11)
H7A1.1267110.5622460.3737970.113*0.418 (11)
C6B0.958 (2)0.5453 (10)0.243 (4)0.0620 (7)0.582 (11)
H6B10.9499100.5547550.1130390.074*0.582 (11)
H6B20.9818560.5783010.3105110.074*0.582 (11)
O7B1.0773 (4)0.5076 (3)0.2653 (10)0.0883 (19)0.582 (11)
H7B1.0869990.4896700.1704710.132*0.582 (11)
C30.8105 (2)0.52358 (8)0.3088 (3)0.0456 (5)
C220.0126 (3)0.25684 (10)0.2520 (5)0.0696 (7)
H22A0.0973100.2531820.1709270.104*
H22B0.0264870.2339810.3582480.104*
H22C0.0770080.2461080.1879400.104*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C120.0373 (9)0.0366 (8)0.0432 (11)0.0002 (7)0.0003 (10)0.0017 (9)
N10.0402 (8)0.0519 (9)0.0397 (10)0.0097 (6)0.0021 (8)0.0082 (9)
C110.0372 (10)0.0377 (8)0.0338 (11)0.0004 (7)0.0020 (8)0.0010 (8)
O160.0706 (10)0.0580 (8)0.0434 (9)0.0082 (7)0.0239 (9)0.0048 (8)
C130.0542 (12)0.0445 (10)0.0508 (13)0.0063 (9)0.0027 (11)0.0063 (10)
C150.0509 (11)0.0427 (10)0.0356 (11)0.0083 (8)0.0067 (10)0.0006 (9)
O190.0912 (14)0.0893 (12)0.0769 (14)0.0107 (10)0.0554 (13)0.0029 (12)
C90.0339 (9)0.0470 (10)0.0388 (11)0.0024 (7)0.0050 (9)0.0057 (9)
N40.0570 (10)0.0593 (10)0.0566 (12)0.0176 (8)0.0027 (11)0.0126 (10)
C100.0372 (9)0.0382 (8)0.0323 (10)0.0039 (7)0.0032 (9)0.0021 (8)
C20.0435 (11)0.0489 (10)0.0389 (11)0.0026 (8)0.0026 (9)0.0026 (9)
N50.0543 (10)0.0618 (11)0.0573 (14)0.0144 (9)0.0083 (10)0.0190 (11)
C170.0573 (13)0.0580 (12)0.0538 (15)0.0130 (10)0.0274 (13)0.0112 (12)
C80.0399 (10)0.0591 (11)0.0426 (12)0.0140 (8)0.0071 (10)0.0021 (11)
C180.0420 (10)0.0566 (11)0.0505 (13)0.0010 (9)0.0124 (11)0.0103 (11)
C200.0354 (9)0.0446 (10)0.0525 (13)0.0069 (7)0.0045 (10)0.0017 (10)
C230.0521 (12)0.0841 (16)0.0572 (16)0.0168 (12)0.0195 (13)0.0131 (14)
C210.0410 (11)0.0788 (15)0.083 (2)0.0002 (10)0.0005 (14)0.0012 (15)
C140.0702 (13)0.0482 (11)0.0409 (12)0.0017 (10)0.0016 (11)0.0120 (10)
C6A0.0507 (13)0.0732 (15)0.062 (2)0.0176 (11)0.0022 (14)0.0079 (14)
O7A0.049 (3)0.085 (4)0.092 (6)0.014 (3)0.016 (3)0.022 (4)
C6B0.0507 (13)0.0732 (15)0.062 (2)0.0176 (11)0.0022 (14)0.0079 (14)
O7B0.0576 (19)0.094 (3)0.113 (4)0.0042 (19)0.029 (2)0.010 (3)
C30.0431 (10)0.0502 (10)0.0434 (12)0.0084 (8)0.0005 (10)0.0036 (10)
C220.0727 (15)0.0572 (13)0.0789 (19)0.0102 (11)0.0213 (16)0.0117 (13)
Geometric parameters (Å, º) top
C12—C111.391 (3)C18—H180.9300
C12—C131.408 (3)C20—C231.524 (4)
C12—C201.531 (3)C20—C221.529 (3)
N1—C21.342 (3)C20—C211.540 (3)
N1—N51.342 (2)C23—H23A0.9600
N1—C81.458 (2)C23—H23B0.9600
C11—C101.402 (3)C23—H23C0.9600
C11—H110.9300C21—H21A0.9600
O16—C171.370 (3)C21—H21B0.9600
O16—C151.383 (3)C21—H21C0.9600
C13—C141.373 (3)C14—H140.9300
C13—H130.9300C6A—O7A1.411 (18)
C15—C141.385 (3)C6A—C31.50 (4)
C15—C101.391 (3)C6A—H6A10.9700
O19—C171.214 (3)C6A—H6A20.9700
C9—C181.346 (3)O7A—H7A0.8200
C9—C101.458 (3)C6B—O7B1.416 (15)
C9—C81.505 (3)C6B—C31.50 (3)
N4—N51.320 (3)C6B—H6B10.9700
N4—C31.355 (3)C6B—H6B20.9700
C2—C31.363 (3)O7B—H7B0.8200
C2—H20.9300C22—H22A0.9600
C17—C181.442 (4)C22—H22B0.9600
C8—H8A0.9700C22—H22C0.9600
C8—H8B0.9700
C11—C12—C13116.66 (19)C22—C20—C21109.52 (19)
C11—C12—C20122.66 (18)C12—C20—C21108.2 (2)
C13—C12—C20120.67 (17)C20—C23—H23A109.5
C2—N1—N5111.27 (16)C20—C23—H23B109.5
C2—N1—C8129.22 (18)H23A—C23—H23B109.5
N5—N1—C8119.51 (17)C20—C23—H23C109.5
C12—C11—C10122.41 (19)H23A—C23—H23C109.5
C12—C11—H11118.8H23B—C23—H23C109.5
C10—C11—H11118.8C20—C21—H21A109.5
C17—O16—C15121.1 (2)C20—C21—H21B109.5
C14—C13—C12122.45 (19)H21A—C21—H21B109.5
C14—C13—H13118.8C20—C21—H21C109.5
C12—C13—H13118.8H21A—C21—H21C109.5
O16—C15—C14116.9 (2)H21B—C21—H21C109.5
O16—C15—C10121.97 (18)C13—C14—C15119.2 (2)
C14—C15—C10121.14 (19)C13—C14—H14120.4
C18—C9—C10118.9 (2)C15—C14—H14120.4
C18—C9—C8124.07 (18)O7A—C6A—C3110 (3)
C10—C9—C8116.99 (17)O7A—C6A—H6A1109.8
N5—N4—C3108.91 (18)C3—C6A—H6A1109.8
C15—C10—C11118.14 (17)O7A—C6A—H6A2109.8
C15—C10—C9117.70 (18)C3—C6A—H6A2109.8
C11—C10—C9124.15 (18)H6A1—C6A—H6A2108.2
N1—C2—C3104.73 (19)C6A—O7A—H7A109.5
N1—C2—H2127.6O7B—C6B—C3112.9 (18)
C3—C2—H2127.6O7B—C6B—H6B1109.0
N4—N5—N1106.58 (18)C3—C6B—H6B1109.0
O19—C17—O16116.7 (3)O7B—C6B—H6B2109.0
O19—C17—C18125.6 (2)C3—C6B—H6B2109.0
O16—C17—C18117.72 (19)H6B1—C6B—H6B2107.8
N1—C8—C9113.38 (18)C6B—O7B—H7B109.5
N1—C8—H8A108.9N4—C3—C2108.50 (18)
C9—C8—H8A108.9N4—C3—C6B120.9 (11)
N1—C8—H8B108.9C2—C3—C6B130.6 (11)
C9—C8—H8B108.9N4—C3—C6A121.5 (15)
H8A—C8—H8B107.7C2—C3—C6A130.0 (15)
C9—C18—C17122.5 (2)C20—C22—H22A109.5
C9—C18—H18118.7C20—C22—H22B109.5
C17—C18—H18118.7H22A—C22—H22B109.5
C23—C20—C22109.0 (2)C20—C22—H22C109.5
C23—C20—C12112.25 (16)H22A—C22—H22C109.5
C22—C20—C12109.95 (17)H22B—C22—H22C109.5
C23—C20—C21107.9 (2)
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C10–C15 ring.
D—H···AD—HH···AD···AD—H···A
O7B—H7B···N4i0.822.493.198 (7)146
C2—H2···O19ii0.932.543.365 (3)147
C23—H23B···O19iii0.962.593.421 (3)146
C22—H22B···Cg3iv0.962.993.818 (3)145
Symmetry codes: (i) x+2, y+1, z1/2; (ii) x, y, z1; (iii) x1, y, z1; (iv) x1/2, y+1/2, z.
 

Acknowledgements

MM thanks the UGC, New Delhi, Government of India, for awarding a project under the title F. No. 41–920/2012(SR) dated: 25–07-2012. SD is grateful to the Council of Scientific and Industrial Research, New Delhi, India, for financial assistance [grant No. 02 (0172)/13/EMR-II].

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