A Synthetic Method to Access Symmetric and Non-Symmetric 2-(N,N'-disubstituted)guanidinebenzothiazoles
Abstract
:1. Introduction
2. Results and Discussion
Comp. | H4 | H5 | H6 | H7 | NH | NCH3, SCH3 | NPh | N(CH2CH2)2 |
---|---|---|---|---|---|---|---|---|
8-NMea | 8.00 | 7.76 | 7.61 | 7.46 | 9.8 | 3.80, 2.66 | ||
9aa | 7.75 | 7.27 | 7.24 | 7.39 | ||||
9bb | 7.58 | 7.46 | 7.31 | 7.24 | 3.62 | |||
10ba | 7.62 | 7.21 | 7.03 | 7.42 | 7.7 | 2.75 | ||
10ca | 7.63 | 7.21 | 7.04 | 7.44 | 8.2 | 3.4, 1.8 | ||
10db | 7.61 | 7.30 | 7.14 | 7.59 | 7.4–7.3 | |||
10eb | 7.69 | 7.30 | 7.17 | 7.63 | 11.2 | 2.97 | 7.5–7.3 | |
10fb | 7.66 | 7.32 | 7.18 | 7.63 | 11.6 | 7.3–7.1 | 3.4, 1.8 | |
10ga | 7.73 | 7.31 | 11.9 | 7.4–7.3 | ||||
10hb | 7.61 | 7.24 | 7.10 | 7.55 | 9.6 | 2.92 | ||
10ib | 7.60 | 7.26 | 7.08 | 7.57 | 8.9 | 3.53 | 3.0, 1.9 | |
10jb | 7.51 | 7.20 | 7.00 | 7.49 | 3.4, 1.8 |
Comp. | C2 | C4 | C5 | C6 | C7 | C8 | C9 | C11 | NCH3, SCH3 | Ph |
---|---|---|---|---|---|---|---|---|---|---|
8-NMea | 166.0 | 114.6 | 124.1 | 124.6 | 128.7 | 126.2 | 138.5 | 175.1 | 33.6, 15.7 | |
9aa | 174.0 | 114.0 | 123.7 | 124.4 | 128.2 | 125.0 | 139.4 | 117.7 | ||
9bb | 171.5 | 112.2 | 122.9 | 124.8 | 127.9 | 123.3 | 139.4 | 116.9 | 31.3 | |
10ba | 158.4 | 125.9 | 122.3 | 121.4 | 118.9 | 130.9 | 152.5 | 174.3 | 28.3 | |
10ca | 155.4 | 125.9 | 122.2 | 121.4 | 119.0 | 130.9 | 152.6 | 174.4 | ||
10db | 156.0 | 125.7 | 122.7 | 122.1 | 119.6 | 131.3 | 151.8 | 173.7 | 136.8, 130.2, 125.7, 127.0 | |
10eb | 154.6 | 125.6 | 122.5 | 121.2 | 119.5 | 131.7 | 151.9 | 174.5 | 28.6 | 137.0, 130.2, 126.9, 126.0 |
10fb | 154.4 | 125.6 | 122.4 | 121.1 | 119.6 | 132.0 | 151.9 | 173.8 | 139.9, 129.5, 125.6, 123.3 | |
10ga | 151.5 | 125.8 | 121.5 | 121.3 | 119.9 | 132.0 | 151.0 | 173.6 | 137.3, 129.8, 123.6, 123.0 | |
10hb | 157.2 | 125.5 | 122.2 | 121.0 | 119.1 | 131.6 | 152.2 | 174.7 | 28.2 | |
10ib | 159.2 | 125.4 | 122.0 | 121.0 | 119.1 | 132.1 | 152.2 | 173.6 | 31.5 | |
10jb | 158.0 | 125.2 | 121.2 | 121.8 | 119.1 | 133.4 | 153.3 | 171.3 |
3. Experimental
3.1. General Procedures
Comp. | Yield (%) | Physical appearance | M.p. (°C) | υ (cm−1) | m/z (%M+) | Elemental analysis Found (calculated) | ||
---|---|---|---|---|---|---|---|---|
C | H | N | ||||||
4 | SM | White solid | 126–129 | |||||
5 | 82 | Yellow powder | 72–73 | 509, 1464 | 254(20) | 47.05(47.24) | 3.95(3.94) | 11.13(11.02) |
9a | 62 | Colorless crystals | 198–199 | 2186, 1600, 1580 | 175(100) | 54.02(54.85) | 3.03(2.85) | 23.73(24.00) |
10b | 88 | White powder | 158–160 | 3406, 3260, 1624 | 206(100) | 52.14(52.42) | 4.88(4.85) | 27.20(27.18) |
10c | 92 | White powder | 242–244 | 3395, 3161, 1609, 1547 | 246(100) | 58.13(58.53) | 5.71(5.69) | 22.40(22.76) |
10d | 76 | White powder | 148–150 | 3436, 3198, 1613, 1568 | 57.42(62.68) | 4.57(4.48) | 19.05(20.89) | |
10e | 89 | White powder | 145–147 | 3418, 3200, 1597, 1560 | 63.14(63.83) | 4.98(4.96) | 19.95(19.86) | |
10f | 90 | Colorless crystals | 184–186 | 3395, 3161, 1609, 1547 | 66.99(67.08) | 5.70(5.59) | 17.72(17.39) | |
10g | 60 | White powder | 127–129 | 3400, 1613, 1580 | 344(19) | 68.19(69.76) | 4.72(4.65) | 16.17(16.28) |
10h | 90 | Brownish liquid | 1602, 1574 | 220(100) | 54.80(54.54) | 5.49(5.45) | 24.24(25.45) | |
10i | 92 | Colorless crystals | 136–137 | 3210, 3080, 1588, 1524 | 59.63(60.0) | 6.24(6.15) | 21.71(21.54) | |
10j | 89 | Brownish liquid | 300(100) | 63.2512(64.00) | 5.9812(6.66) | 19.12(18.66) |
Compound | 10f | 10i | 9a |
---|---|---|---|
Unit cell information | |||
Cell axes [Å]a | 11.3477[13] | 14.3400[20] | 5.6230[10] |
b | 9.0463[11] | 7.8188[12] | 8.2300[9] |
c | 16.5004[19] | 24.1730[40] | 17.2290[10] |
Cell angles [deg]α | 90.000[0] | 90.000[0] | 90.000[0] |
β | 101.858[2] | 101.858[2] | 90.000[0] |
γ | 90.000[0] | 90.000[0] | 90.000[0] |
Crystal system | Monoclinic | Orthorhombic | Monoclinic |
Space group | P 2l/c | P na2l | P 2l/c |
Molecular Formula | C18H18N4S | C13H16N4S | C8H5N3S |
Density [g cm−1] | 1.29 | 1.28 | 1.46 |
Formula weight | 322.4 | 520.7 | 175.2 |
No. Form. Units Z | 4 | 4 | 4 |
Reflection data | |||
No. Meas. | 15334 | 22566 | 3406 |
No. Uniq. | 2920 | 4245 | 1544 |
No. Obs. | 2630 | 3049 | 1278 |
Current refinement | |||
No. Reflen. | 2920 | 4245 | 1544 |
No. Param. | 208 | 325 | 110 |
Delta-rho[eÅ−3]max, min | 0.242, −0.280 | 0.922, −0.272 | 0.274, −0.283 |
R_all, R_obs | 0.054, 0.049 | 0.102, 0.073 | 0.054, 0.049 |
wR2_all, wR2_aobs | 0.125, 0.121 | 0.189, 0.166 | 0.127, 0.116 |
3.2. General Procedure to Get Isothiourea Intermediates 8
3.3. General Procedure to Obtain Guanidines 10
4. Conclusions
Acknowledgments
References
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Cruz, A.; Padilla-Martínez, I.I.; García-Báez, E.V. A Synthetic Method to Access Symmetric and Non-Symmetric 2-(N,N'-disubstituted)guanidinebenzothiazoles. Molecules 2012, 17, 10178-10191. https://doi.org/10.3390/molecules170910178
Cruz A, Padilla-Martínez II, García-Báez EV. A Synthetic Method to Access Symmetric and Non-Symmetric 2-(N,N'-disubstituted)guanidinebenzothiazoles. Molecules. 2012; 17(9):10178-10191. https://doi.org/10.3390/molecules170910178
Chicago/Turabian StyleCruz, Alejandro, Itzia I. Padilla-Martínez, and Efrén V. García-Báez. 2012. "A Synthetic Method to Access Symmetric and Non-Symmetric 2-(N,N'-disubstituted)guanidinebenzothiazoles" Molecules 17, no. 9: 10178-10191. https://doi.org/10.3390/molecules170910178