新型馬來(lái)松香基雙官能化合物的合成及其抑菌活性

董淑求， 段文貴， 岑 波， 許雪棠， 韋有杰， 李龍生

(廣西大學(xué) 化學(xué)化工學(xué)院,廣西 南寧 530004)

松香是我國(guó)的一項(xiàng)優(yōu)勢(shì)資源，廣泛應(yīng)用于油墨、合成原料、油漆、肥皂等行業(yè)中。其改性產(chǎn)品也越來(lái)越受到人們的重視[1～4]，馬來(lái)松香是重要的改性產(chǎn)品之一。以其為原料可以制備性能良好的抗菌劑、表面活性劑、防銹劑、功能材料、涂料等[5～10]。噁二唑雜環(huán)化合物近年受到人們的廣泛關(guān)注[11,12]，具有殺蟲(chóng)、抗菌等生物活性[13,14]。有關(guān)酰胺類(lèi)化合物的研究報(bào)道也較多，其具有較好的除草和抑菌等生物活性[15～17]。

本文以松香為原料合成了馬來(lái)松香(1); 1經(jīng)酰氯化、肼解和酰化反應(yīng)制得馬來(lái)松香雙酰肼(4a～4g);以三氯氧磷為脫水劑，4a～4g關(guān)環(huán)合成了7個(gè)新型的馬來(lái)松香基雙官能化合物(5a～5g, Scheme 1)，其結(jié)構(gòu)經(jīng)1H NMR，13C NMR， IR和MS 表征。初步抑菌活性測(cè)試結(jié)果表明5a～5g對(duì)黃瓜枯萎病菌、蘋(píng)果輪紋病菌、番茄早疫病菌、花生褐斑病菌和小麥赤霉病菌均有一定殺菌活性(尤其是對(duì)蘋(píng)果輪紋病菌)。

CompabcdefgArC6H5-4-CH3C6H4-4-O2NC6H4-4-MeOC6H4-2-ClC6H4-4-ClC6H4-3-FC6H4-

Scheme1

1 實(shí)驗(yàn)部分

1．1 儀器與試劑

X-4型數(shù)字顯示顯微熔點(diǎn)儀(溫度未校正)；Bruker AV 600 MHz型核磁共振儀(DMSO-d6為溶劑，TMS為內(nèi)標(biāo))；Nicolet Nexus 470 FT-IR型紅外光譜儀(KBr壓片)；Agilent 1100 LC/MSD Trap SL型高效液相色譜-質(zhì)譜聯(lián)用儀。

1[18]和馬來(lái)松香酸酰氯(2)[9]按文獻(xiàn)方法合成；特級(jí)松香，廣西梧州松脂股份有限公司；其余所用試劑均為分析純。

1．2 合成

(1) 馬來(lái)松香酰肼(3)的合成

在反應(yīng)瓶中加入80%水合肼10 mL和CH2Cl250 mL，攪拌下于室溫緩慢加入2 10 mmol的CH2Cl2(20 mL)溶液，反應(yīng)5 h(TLC監(jiān)測(cè))。加入飽和氯化鈉溶液50 mL，分液，有機(jī)相旋蒸脫溶，殘余物用乙醇重結(jié)晶得白色固體馬來(lái)松香酰肼(3)，收率70%， m.p.255 ℃～258 ℃；1H NMRδ： 8.81(s, 1H, NH), 5.33(s, 1H, 14-H), 4.83(d,J=9.3 Hz, 2H, NH2), 4.21(s, 2H, NH2), 2.86(d,J=1.5 Hz, 1H, 21-H), 2.81(dd,J=7.8, 2.8 Hz, 1H, 22-H), 2.45(d,J=7.9 Hz, 1H, 12-H), 2.34(dd,J=10.6, 3.1 Hz, 1H, 5-H), 2.11(m, 1H, CH ini-Pr), 1.80(m, 1H, 9-H), 1.73～1.24(m, 10H, CH2), 1.09(s, 2H, CH2), 1.04(s, 3H, 18-H), 0.89(m, 6H, CH3ini-Pr), 0.53(s, 3H, 20-H)；13C NMRδ： 177.27, 175.24, 174.55, 146.13, 124.29, 53.33, 53.21, 50.24, 48.96, 45.16, 42.78, 37.63, 37.20, 36.44, 35.05, 34.96, 32.22, 27.16, 20.72, 20.66, 20.16, 16.81, 16.28, 15.53； IRν： 3 345, 3 283, 3 245, 1 777, 1 698, 1 623, 1 515 cm-1； ESI-MSm/z: 429{[M+H]+}。

(2)4a～4g的合成(以4a為例)

在反應(yīng)瓶中加入35 mmol， THF 25 mL，攪拌下于回流狀態(tài)緩慢滴加苯甲酰氯(Ⅰa)10 mmol的THF(20 mL)溶液，滴畢，反應(yīng)2 h(TLC監(jiān)測(cè))。旋蒸脫溶，殘余物經(jīng)硅膠柱層析[洗脫劑：A=V(乙酸乙酯) ∶V(石油醚)=1 ∶2]純化得白色固體4a。

用類(lèi)似方法合成白色固體4b～4g，其表征數(shù)據(jù)分別見(jiàn)表1和表2。

(3)5a～5g的合成(以5a為例)

在反應(yīng)瓶中加入45 mmol，乙腈25 mL，攪拌下緩慢滴加三氯氧磷3.07 g(20 mmol)的乙腈(20 mL)溶液，滴畢，回流反應(yīng)3 h(TLC監(jiān)測(cè))。傾入冰水中(析出沉淀)，靜置，過(guò)濾，濾餅經(jīng)硅膠柱層析(洗脫劑：A=1 ∶3)純化得白色固體5a。

用類(lèi)似方法合成白色固體5b～5g，其表征數(shù)據(jù)分別見(jiàn)表1和表2。

1．3 5的抑菌活性測(cè)試

將供試藥劑溶解在丙酮中，用2×10-4mg·L-1sorporl-144乳化劑稀釋成5×10-4mg·L-1藥液。取藥液1 mL，注入培養(yǎng)皿內(nèi)，加入PSA培養(yǎng)基9 mL，制成最終濃度為5×10-5mg·L-1含藥平板。將培養(yǎng)好的供試菌用打孔器打取直徑5 mm菌餅，置于含藥平板內(nèi)，每皿三塊呈等邊三角形擺放。以不加藥劑做空白對(duì)照。將各處理于(24±1) ℃培養(yǎng)箱內(nèi)培養(yǎng)48 h，計(jì)量各處理菌絲擴(kuò)展直徑，并與對(duì)照相比較，計(jì)算相對(duì)抑菌率，結(jié)果見(jiàn)表3。

2 結(jié)果與討論

2．1 合成

(1)4a～4g的合成

3與Ⅰa～Ⅰg的反應(yīng)分兩步進(jìn)行。 TLC監(jiān)測(cè)發(fā)現(xiàn)滴加Ⅰ時(shí)，開(kāi)始有一個(gè)新產(chǎn)物生成，繼續(xù)滴加該新點(diǎn)消失，生成另一個(gè)新點(diǎn)，可能是由于酰肼的活性大于環(huán)酰亞胺的活性。另外，實(shí)驗(yàn)發(fā)現(xiàn)該反應(yīng)易于進(jìn)行，不需要添加縛酸劑或催化劑。

(2)5a～5g的合成

4可以用多聚磷酸、三氯氧磷等脫水關(guān)環(huán)，實(shí)驗(yàn)發(fā)現(xiàn)，用三氯氧磷效果較好、雜質(zhì)較少。另外，溫度對(duì)反應(yīng)影響較大，于乙腈回流溫度反應(yīng)較快。

2．2 表征

在4的IR譜圖中， 3 000 cm-1以上為N-H吸收峰， 1 720 cm-1和1 795 cm-1處為酰亞胺五元環(huán)上兩個(gè)羰基C=O的伸縮振動(dòng)特征吸收峰， 1 630 cm-1為酰胺羰基振動(dòng)吸收峰， 1 500 cm-1為苯環(huán)骨架伸縮振動(dòng)吸收峰；1H NMR和13C NMR分析表明， 9.5～11.0的三個(gè)吸收峰為N-H， ArH吸收峰位于7.0～8.2，苯環(huán)上碳吸收峰在123～150。 由ESI-MS結(jié)果可見(jiàn)4的分子離子峰或者準(zhǔn)分子離子峰。

在5的IR譜圖中， 1 550 cm-1為C=N的吸收峰。1H NMR分析結(jié)果表明N-H在11附近只剩一個(gè)吸收峰，說(shuō)明有兩個(gè)質(zhì)子氫脫去，發(fā)生了環(huán)合反應(yīng)。 ESI-MS結(jié)果可見(jiàn)5的分子離子峰或者準(zhǔn)分子離子峰。

表1 4和5的實(shí)驗(yàn)結(jié)果，MS和IR數(shù)據(jù)Table 1 Experimental results, MS and IR data of 4 and 5

表 2 4和5的NMR數(shù)據(jù)Table 2 NMR data of 4 and 5

續(xù)表2

Comp1H NMR δ(J/Hz)13C NMR δ4f11.09(s, 1H, NH), 10.28(s, 1H, NH), 9.62(s, 1H, NH), 7.91(d, J=8.6, 4H, ArH), 7.61(d, J=8.2, 2H, ArH), 7.58(d, J=8.5, 2H, ArH), 5.46(s, 1H, 14-H), 3.10(m, 1H, 21-H), 2.96(s, 1H, 22-H), 2.69(m, 1H, 12-H), 2.32(t, J=15.8, 1H, 5-H), 2.17(m, 1H, CH in i-Pr), 1.81(t, J=11.4, 1H, 9-H), 1.78～1.68(m, 2H, CH2), 1.67～1.30(m, 8H, CH2), 1.16(m, 2H, CH2), 1.14(d, J=7.8, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.59(s, 3H, 20-H)177.32, 174.72, 173.93, 164.74, 163.58, 146.26, 137.50, 136.56, 131.53, 129.73, 129.36, 128.82, 128.59, 124.46, 124.22, 53.26, 50.34, 50.24, 49.03, 45.75, 42.88, 37.49, 37.43, 36.33, 34.96, 34.86, 32.31, 27.05, 20.49, 20.02, 18.59, 16.82, 16.58, 15.534g11.11(s, 1H, NH), 10.26(d, 1H, NH), 9.63(d, 1H, NH), 7.77～7.70(m, 2H, ArH), 7.67(dt, J=10.9, 5.8, 2H, ArH), 7.62～7.54(m, 2H, ArH), 7.50(t, J=7.6, 1H, ArH), 7.43(td, J=8.4, 2.2, 1H, ArH), 5.46(s, 1H, 14-H), 3.11(m, 1H, 21-H), 2.96(s, 1H, 22-H), 2.70(m, 1H, 12-H), 2.32(t, J=15.4, 1H, 5-H), 2.17(m, 1H, CH in i-Pr), 1.82(dd, J=13.3, 9.3, 1H, 9-H), 1.76(d, J=12.2, 2H), 1.68～1.47(m, 4H, CH2), 1.47～1.33(m, 4H, CH2), 1.16(dd, J=13.2, 6.0, 2H, CH2), 1.14(d, J=7.1, 3H, 18-H), 0.99～0.92(m, 6H, CH3 in i-Pr), 0.59(s, 3H, 20-H)177.50, 174.76, 173.78, 164.28, 163.31, 146.43, 135.09, 130.98, 130.75, 124.50, 124.04, 123.87, 123.60, 119.70, 119.55, 118.74, 118.60, 114.30, 114.14(C-D), 53.55, 53.27, 50.25, 49.03, 45.76, 42.94, 37.57, 37.43, 36.33, 34.95, 34.87, 32.30, 27.06, 20.49, 20.03, 19.43, 16.82, 16.58, 15.535a10.97(s, 1H, NH), 8.06～7.96(m, 2H, ArH), 7.84(m, 2H, ArH), 7.61(d, J=7.4 Hz, 4H), 7.51(t, J=7.3 Hz, 2H), 5.47(s, 1H, 14-H), 3.10(d, J=8.3 Hz, 1H, 21-H), 2.98(s, 1H, 22-H), 2.77(m, 1H, 12-H), 2.28(d, J=11.7 Hz, 1H, 5-H), 2.23～2.12(m, 1H, CH in i-Pr), 1.89(m, 1H, 9-H), 1.82(m, 2H, CH2), 1.79～1.44(m, 8H, CH2), 1.43(s, 2H, CH2), 1.07～1.00(m, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.67(s, 3H, 20-H)174.68, 173.83, 173.43, 164.54, 163.75, 146.60, 132.53, 131.79, 131.01, 129.38, 128.58, 127.77, 127.62, 126.46, 123.66, 53.24, 52.94, 50.51, 49.86, 45.17, 42.84, 37.74, 37.52, 34.93, 34.78, 34.59, 32.29, 27.11, 20.68, 20.49, 20.00, 17.30, 16.56, 15.485b10.87(s, 1H, NH), 7.90(d, J=8.2 Hz, 2H, ArH), 7.77(d, J=8.0 Hz, 1H, ArH), 7.73(d, J=7.6 Hz, 1H, ArH), 7.41(d, J=8.2 Hz, 2H, ArH), 7.31(d, J=7.7 Hz, 2H, ArH), 5.46(s, 1H, 14-H), 3.07(t, J=10.8 Hz, 1H, 21-H), 2.97(s, 1H, 22-H), 2.75(m, 1H, 12-H), 2.38(m, 6H, CH3-Ar), 2.32～2.23(m, 1H, 5-H), 2.17(dd, J=13.3, 6.4 Hz, 1H, CH in i-Pr), 1.91～1.85(m, 1H, 9-H), 1.48(m, 12H, CH2), 1.02(s, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.66(s, 3H, 20-H)174.64, 173.89, 173.07, 164.38, 163.83, 146.57, 129.92, 129.32, 129.13, 129.09, 128.21, 127.81, 127.65, 126.42, 124.27, 52.94, 50.69, 50.52 49.84, 45.43, 42.83, 37.74, 37.53, 36.67, 34.94, 34.62, 32.29, 27.11, 21.12, 21.04, 20.68, 20.49, 20.00, 17.31, 16.57, 15.485c11.36(s, 1H, NH), 8.46～8.39(m, 2H, ArH), 8.36(d, J=8.2, 2H, ArH), 8.30～8.24(m, 2H, ArH), 8.08(d, J=8.6, 2H, ArH), 5.47(s, 1H, 14-H), 3.17～3.06(m, 1H, 21-H), 2.99(s, 1H, 22-H), 2.77(m, 1H, 12-H), 2.27(d, J=12.8, 1H, 5-H), 2.18(d, J=6.4, 1H, CH in i-Pr), 1.89(dt, J=13.4, 6.8, 1H, 9-H), 1.86～1.40(m, 12H, CH2), 1.09～0.99(m, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.67(s, 3H, 20-H)174.44, 173.58, 173.46, 163.14, 162.57, 149.78, 149.08, 146.66, 136.45, 130.71, 129.36, 129.29, 127.89, 124.57, 123.85, 52.95, 50.64, 50.53, 49.96, 42.87, 37.77, 37.70, 37.48, 34.95, 34.58, 32.29, 27.10, 20.63, 20.50, 20.01, 17.28, 16.53, 15.48

續(xù)表2

Comp1H NMR δ(J/Hz)13C NMR δ5d10.79(s, 1H, NH), 7.97～7.92(m, 2H, ArH), 7.85(d, J=8.7, 2H, ArH), 7.17～7.11(m, 2H, ArH), 7.04(d, J=8.6, 2H, ArH), 5.46(s, 1H, 14-H), 3.83(m, 6H, CH3O), 3.07(t, J=10.8, 1H, 21-H), 2.97(s, 1H, 22-H), 2.74(m, 1H, 12-H), 2.35～2.24(m, 1H, 5-H), 2.21～2.08(m, 1H, CH in i-Pr), 1.89～1.84(m, 1H, 9-H), 1.84～1.62(m, 4H, CH2), 1.47(d, J=82.0, 8H, CH2), 1.02(d, J=5.6, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.66(s, 3H, 20-H) 174.82, 173.98, 172.87, 163.62, 161.89, 129.81, 129.62, 129.48, 128.27, 124.27, 123.11, 116.07, 114.83, 113.81, 55.51, 55.45, 53.26, 52.97, 50.46, 49.85, 42.83, 37.75, 37.54, 34.94, 34.80, 34.63, 32.30, 27.01, 20.66, 20.50, 20.00, 17.33, 16.58, 15.485e11.01(s, 1H, NH), 7.98(dd, J=7.8, 1.5, 1H, ArH), 7.72(d, J=8.1, 1H, ArH), 7.66(td, J=7.8, 1.7, 1H, ArH), 7.58(td, J=7.6, 1.1, 1H), 7.53(m, 2H, ArH), 7.48(dd, J=7.6, 1.6, 1H, Ar), 7.46～7.41(m, 1H, ArH), 5.40(s, 1H, 14-H), 3.08(m, 1H, 21-H), 2.96(s, 1H, 22-H), 2.75(m, 1H, 12-H), 2.34(s, 1H, 5-H), 2.18～2.09(m, 1H, CH in i-Pr), 1.85(dd, J=13.3, 3.6, 1H, 9-H), 1.43(s, 12H, CH2), 1.02(m, 3H, 18-H), 0.92(m, 6H, CH3 in i-Pr), 0.66(s, 3H, 20-H)174.36, 173.99, 173.31, 162.21, 162.09, 147.08, 133.22, 132.02, 131.84, 131.40, 130.99, 130.48, 129.50, 127.93, 127.22, 124.26, 123.04, 52.87, 50.70, 50.03, 49.60, 45.94, 42.81, 37.77, 37.56, 36.79, 35.15, 34.62, 32.27, 27.14, 20.72, 20.52, 19.96, 17.29, 16.56, 15.475f11.09(s, 1H, NH), 8.03(d, J=8.5, 2H, ArH), 7.89(d, J=8.3, 2H, ArH), 7.72～7.65(m, 2H, ArH), 7.61(d, J=8.1, 2H, ArH), 5.47(s, 1H, 14-H), 3.10(m, 1H, 21-H), 2.98(s, 1H, 22-H), 2.76(m, 1H, 12-H), 2.28(d, J=11.4, 1H, 5-H), 2.21～2.11(m, 1H, CH in i-Pr), 1.88(m, 1H, 9-H), 1.84～1.62(m, 4H, CH2), 1.60～1.41(m, 8H, CH2), 1.02(d, J=6.3, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.67(s, 3H, 20-H)174.62, 173.77, 173.65, 163.60, 163.07, 146.64, 137.47, 136.52, 131.16, 129.73, 129.57, 128.80, 128.76, 128.32, 124.29, 52.94, 50.49, 49.99, 49.89, 42.85, 37.75, 37.50, 34.96, 34.84, 34.59, 32.32, 27.12, 20.66, 20.52, 20.03, 17.30, 16.56, 15.495g11.10(d, J=24.1, 1H, NH), 7.87(dd, J=7.8, 1.0, 1H, ArH), 7.83～7.77(m, 1H, Ar),7.74～7.54(m, 4H, Ar), 7.52～7.44(m, 2H, ArH), 5.47(s, 1H, 14-H), 3.11(d, J=8.4, 1H, 21-H), 2.98(s, 1H, 22-H), 2.77(m, 1H, 12-H), 2.27(d, J=12.2, 1H, 5-H), 2.21～2.11(m, 1H, CH in i-Pr), 1.88(dd, J=18.2, 14.4, 1H, 9-H), 1.42～1.83(m, 12H, CH2), 1.05(s, 3H, 18-H), 0.96(m, 6H, CH3 in i-Pr), 0.66(s, 3H, 20-H)174.56, 173.85, 173.10, 162.90, 161.47, 146.61, 133.16, 131.84, 131.01, 125.75, 125.45, 124.35, 124.04, 122.77, 119.55, 118.88, 115.66, 114.58, 113.13, 53.19, 52.89, 50.41, 49.87, 42.86, 37.75, 37.68, 37.48, 34.92, 34.53, 32.30, 27.11, 20.51, 20.03, 19.41, 17.28, 16.56, 15.48

2．3 抑菌活性

4和5在用藥量為50 μg·mL-1時(shí)對(duì)黃瓜枯萎病菌、蘋(píng)果輪紋病菌、番茄早疫病菌、花生褐斑病菌和小麥赤霉病菌具有不同程度的抑制作用，結(jié)果列于表3。從表3可知，4和5對(duì)測(cè)試病菌均有一定的抑制作用，尤其是對(duì)蘋(píng)果輪紋病菌抑制效果較好。

表 3 4和5的抑菌活性*Table 3 Fungicidal activity of 4 and 5

*A:Fusariumoxysporumf.sp.cucumerinum, B:Physalosporapiricola, C:Alternariasolani, D: Cercospora rachidicola,E: Fusarium graminearum

[1] 朱巖, 任瑩. 改性松香水分散液的制備及其粘合性能研究[J].精細(xì)化工,2010,27(4) :405-408.

[2] Duan W G, Shen C M, Fang H X,etal. Synthesis of dehydroabietic acid-modified chitosan and its drug release behavior[J].Carbohydrate Research,2009,344(1):9-13.

[3] 李雙月. 幾種抑木腐菌活性松香衍生物的合成與表征[D].黑龍江:東北林業(yè)大學(xué)碩士學(xué)位論文,2009.

[4] 田小艷, 楊達(dá), 潘英明, 等. 含脫氫松香酸骨架的吖啶染料的合成及其理化性質(zhì)研究[J].有機(jī)化學(xué),2011,31(3):346-355.

[5] Hess S C, Farah M I, Eguchib S Y,etal. Synthetic studies with pinus elliottiis′rosin derivatives oxidation of maleopimaric anhydride methyl ester and trimethyl

fumaropimarate[J].J Braz Chem Soc,2000,11(1):59-63.

[6] Panda R, Panda H. Mold growth inhibitor from maleopimaric acid[J].Chemistry and Industry of Forest Products,1995,15(1):40-42.

[7] 崔錦峰, 康博, 楊保平, 等. 馬來(lái)松香-聚氧乙烯醚雙酯羧酸鈉表面活性劑[J].蘭州理工大學(xué)學(xué)報(bào),2009,35(6):64-67.

[8] 王慧媛.新型防銹劑馬來(lái)海松酸醇酰胺的制備及其應(yīng)用研究[D]. 南京:南京理工大學(xué)碩士學(xué)位論文,2009.

[9] Jong S L, Sung H. Synthesis of acrylic rosin derivatives and application as negative photoresist[J].European Polymer Journal,2002,38:387-392.

[10] Atta A M, El-Saeed S M, Farag R K. New vinyl ester resins based on rosin for coating applications[J].Reactive and Functional Polymers,2006,66:1596-1608.

[11] Lv H S, Zhao B X, Li J K,etal. The synthesis， characterization and optical properties of novel, substituted, pyrazoly 1,3,4-oxadiazole derivatives[J].Dyes and pigments,2010,86:25-31.

[12] Gilani S, Khan S, Siddiqui N. Synthesis and pharmacological evaluation of condensed heterocyclic 6-substituted 1,2,4-triazolo-[3,4-b]-1,3,4-oxadiazole derivatives of isoniazid[J].Bioorganic and Medicinal Chemistry Letters,2010,20:4762-4765.

[13] 馬獻(xiàn)力, 陳麗, 段文貴, 等. 脂肪族二酸二烷基雙去氫樅基雙噁二唑的合成及除草活性[J].有機(jī)化學(xué),2011,31(7):1069-1075.

[14] Chandrakantha B, Shetty P, Nambiyar V,etal. Synthesis, characterization and biological activity of some new 1,3,4-oxadiazole bearing 2-flouro-4-methoxy phenyl moiety[J].European Journal of Medical Chemistry,2010,45: 1206-1210.

[15] 李宇彬,段文貴,陳秋菊,等. 丙烯海松酸基雙酰胺類(lèi)化合物的合成及生物活性研究[J].化學(xué)試劑,2012,34(1):9-15,54.

[16] 鄒榮霞, 岑波, 段文貴, 等. 蒎酸基雙苯酰胺類(lèi)化合物的合成及其除草活性[J].廣西大學(xué)學(xué)報(bào)，2011,36(3):463-469.

[17] 李歡歡, 王振軍, 王力鐘, 等.α-取代苯乙酰胺類(lèi)化合物的合成及生物活性[J].高等學(xué)?；瘜W(xué)學(xué)報(bào),2011,32(1):79-83.