the tetra substituted cyclohexane compositions of the present invention are designed to have an intramolecular charge transfer chromogen and ionophore . basically , the purpose of the composition is to complex the various metal ions such as alkali metal ions , alkaline earth metal ions and ammonium ions and to effect a change in the uv - visible spectrum upon complexation . the alkali metal ions include lithium , sodium , potassium and the like . the alkaline earth metal ions include calcium , magnesium , strontrum , barium and the like . ammonium ions are the fluid soluble ammonium ions that result from dissolving primary and secondary amines . the amine containing materials are alkyl amines , aralkyl amines and the hydroxy and carboxy derivatives thereof of from 6 - 20 carbon atoms . suitable amines are para - 3 - amino propyl benzyl amine ; amino acids may be cystine , phenylalanine , tyrosine , halogenated tyrosines , thyronine , halogenated thyronines , proline , tryptophan and the like . synthetic ionophores are materials that are capable of forming complexes with charged species , primarily cations . the common features shared by all ionophores are 1 ) the presence of an array of heteroatoms containing electron pairs capable of forming donor - acceptor complexes with cations and 2 ) a flexible hydrocarbon backbone capable of solvating the complex in both polar and nonpolar solvents . the geometry of the hydrocarbon backbone contained in synthetic ionophores facilitates their classification into three categories : acyclic podands ( i . e . polyethers ), monocyclic coronands ( i . e . crown ethers ) and multicyclic cryptands . examples of each class are : pentaethylene glycol diethyl ether , 18 - crown - 6 , an elipsoidal [ 2 . 2 . 2 ] cryptand , kryptofix - s , tetrathia - 12 - crown - 4 , and a spherical cryptand . this case is further concerned with charge transfer complexes or switchable intramolecular charge - transfer complexes ( sometimes called electron donor - acceptor complexes , mulliken , r . s ., j . am . chem . soc . 1952 , 74 , 811 , herein incorporated by reference ). these complexes give rise to absorption bands that are not present in the two parent compounds that form the complex . the intensity of these absorption bands ( and the extent of intramolecular complexation ) can be controlled by changing the relative molecular geometry of the complex framework , which is accomplished by chemical manipulation of the parent compounds . the interaction of a molecule of high electron affinity with another molecule possessing low ionization potential may give rise to a molecular complex ( or charge transfer complex ) possessing properties not found in either component substance . these properties are : 1 ) new electronic absorption bands , 2 ) a loss in diamagnetic susceptibility , and 3 ) an increase in paramagnetic susceptibility ( the presence of unpaired electrons ). the purpose of the compositions is to permit the detection of these ions in fluids such as aqueous or non - aqueous liquids , mammallian body liquids such as blood , urine and the like and other liquid fluids in which the metal ions are dissolved such as liquid hydrocarbons , liquid halogenated hydrocarbons from one to six carbon atoms , aliphatic alcohols or esters , aliphatic glycols or glycol ethers , heterocyclic solvents such as dioxane , furan , pyridine and mixtures thereof . having described the invention , listed below are preferred embodiments wherein all parts are parts by weight and all temperatures are in degrees centigrade unless otherwise indicated . the product was a result of the stepwise reaction scheme illustrated in fig1 . a . 1 , 4 - cyclohexadiene ( 50 . 0 g , 0 . 626 mol ) was added to a mixture of 225 ml of distilled water and 25 ml of ρ - dioxane . the mixture was stirred at 25 ° c . and n - bromo succinimide ( 108 . 9 g , 0 . 612 mol ) was added slowly over a 1 hour period . the mixture was allowed to stir an additional 3 hours . the reaction mixture was then extracted 3 times with 100 ml portions of chloroform . the combined organic layers were then extracted 3 times with 50 ml portions of saturated aqueous sodium bicarbonate then dried over sodium sulfate and filtered . the solvent was removed in vacuo and the crude bromohydrin was immediately added to 1050 ml of a freshly prepared 1 . 0 n sodium hydroxide solution and allowed to stir for 1 hour at 25 ° c . the reaction mixture was extracted three times with 100 ml portions of chloroform and the combined organic layers were dried over sodium sulfate and filtered . the solvent was removed in vacuo giving the crude epoxide which was distilled at 5 mm hg . the fraction collected at 38 °- 40 ° c . ( 58 . 5 g , 97 %) was shown to be subreaction product 1 : [ 4 . 1 . 0 ] bicyclo - 7 - oxo - hept - 3 - ene . b . to 126 ml of a 6n solution of potassium hydroxide was added 15 ml of ρ - dioxane and 123 . 4 g ( 243 . 6 mmol ) of [ 4 . 1 . 0 ] bicyclo - 7 - oxo - hept - 3 - ene . the stirred mixture was allowed to reflux for 24 hours and then cooled to room temperature . 150 ml of brine was added and the mixture was extracted 7 times with 50 ml aliquots of chloroform . the combined organic layers were dried over sodium sulfate and the solvent was removed in vacuo . the resulting oil solidified upon standing giving the crude diol . the diol was dissolved in hot ethyl acetate , decolorized with activated charcoal and recrystallized from hot 75 % ethyl acetate / 25 % heptane to give subreaction product 2 , [ 1 ( r , s ), 2 ( r , s )] 4 - cyclohexen - 1 , 2 - diol as white crystals , 15 . 9 g ( 57 . 4 %). c . a 3 neck flask was fitted with a magnetic stirrer , a condenser and an addition funnel . the flask was flame dried and constantly purged with dry nitrogen . to the flask , 300 ml of dry thf and sodium hydride ( 2 . 78 g , 1 . 1 equiv ., 50 % oil dispersion , washed twice with hexane ) were added and allowed to stir . [ 1 ( r , s ), 2 ( r , s )] 4 - cyclohexen - 1 , 2 - diol ( 3 . 0 g , 26 . 3 mmol ) and 18 - crown - 6 ( 0 . 10 g , catalyst ) were added to the solution and stirred for 4 hours . the flask was put in a brine - ice bath (- 5 ° c .) and 2 -( 2 - ethoxyethoxy ) ethyl ρ - toluene sulfonate ( 17 . 42 g , 1 . 15 equiv .) was dissolved in 50 ml of dry thf and added dropwise over a 2 hour period . the solution was warmed to room temperature and the flask was fitted with a heating mantle . the solution was heated and allowed to reflux for 48 hours , then cooled . the mixture was filtered and the solvent removed in vacuo . the product was separated by flash column chromatography ( 300 g silica gel , 40 % ethyl acetate / 60 % petroleum ether rising to 75 % ethyl acetate / 25 % petroleum ether , tlc : r f diol = 0 . 31 , r f product = 0 . 39 , in 50 / 50 ethoac / pet eth ) giving subreaction product 3 , 4 ( s , r ), 5 ( s , r )- 4 , 5 - bis ( 1 , 4 , 7 - trioxononanyl )- cyclohex - 1 - ene as a clear - yellowish oil ( 3 . 7 g , 41 %). the 2 -( 2 - ethoxyethoxy ) ethyl ρ - toluene sulfonate was prepared as follows : pyridine ( 75 ml ) was added to a flask containing ρ - toluene sulfonyl chloride ( 16 . 0 g , 0 . 085 mol ) and swirled until the solid dissolved . the mixture was cooled to 0 ° c . and 2 -( 2 - ethoxyethoxy ) ethanol ( 11 . 4 g , 0 . 085 mol ) was added . the mixture was stirred for 3 hours and 10 % sulfuric acid added until the ph of the solution was 5 or less . the solution was then extracted 3 times with ether and the combined organic layers were dried over sodium sulfate . the solvent was removed in vacuo leaving an oil that was shown to be pure 2 -( 2 - ethoxyethoxy ) ethyl ρ - toluene sulfonate ( 16 . 1 g , 55 %, 0 . 047 mol ). d . a 250 ml flask was flame dried and fitted with a drying tube and a magnetic stirrer . the flask was then charged with 125 ml of methylene chloride , 4 ( s , r ), 5 ( s , r )- 4 , 5 - bis ( 1 , 4 , 7 - trioxononanyl )- cyclohex - 1 - ene -( 1 . 5 g , 4 . 33 mmol ) and chilled in an ice bath . the solution was allowed to stir for 15 minutes , then meta - chloroperoxy - benzoic acid ( 80 %, 1 . 51 g , 8 . 5 mmol ) was added and the solution was stirred for 2 hours . the reaction mixture was then warmed slowly to room temperature and allowed to stir overnight . the solvent was removed in vacuo while maintaining the bath temperature below 30 ° c . and the remaining oil was dissolved in 100 ml of ether . the organic solution was extracted 3 times with 20 % aqueous sodium bisulfite , 3 times with saturated sodium bicarbonate and once with brine . the organic layer was dried over sodium sulfate and the solvent removed in vacuo . the crude oil was purified using flash chromatography ( 150 g silica gel , 40 % ethyl acetate / 60 % petroleum ether yielding 1 . 263 g ( 64 %) 1 ( r , s ), 2 ( s , r ), 4 ( s , r ), 5 ( s , r )- 4 , 5 - bis ( 1 , 4 , 7 - trioxononanyl )- cyclohex - 1 - ene oxide ( subreaction product 4 ), as a clear , white oil . e . a 100 ml flask was flame dried and purged with dry nitrogen . the flask was fitted with a condenser , magnetic stirrer and charged with 25 ml of tert - butyl alcohol . 4 - methylthiophenol ( 4 equivalents ) was dissolved in 25 ml of dry thf and added to the reaction flask . to the solution , potassium tert - butoxide ( 0 . 747 g , 4 . 0 equivalents ) was added and the solution was allowed to stir for 20 minutes . 1 ( r , s ), 2 ( s , r ), 4 ( s , r ), 5 ( s , r )- 4 , 5 - bis ( 1 , 4 , 7 - trioxononanyl )- cyclohex - 1 - ene oxide ( 0 . 655 g , 1 . 81 mmol ) was added to the mixture , the flask was fitted with a heating mantle and the mixture was warmed and allowed to reflux for 4 days . the solvent was removed in vacuo and the residue was dissolved in diethyl ether . the organic solution was extracted 3 times with 10 % sodium hydroxide , once with brine and dried over magnesium sulfate . the solvent was removed in vacuo leaving pure 2 -( 4 - methylthiophenoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- 1cyclohexanol ( subreaction product 5 ) as a clear oil ( 92 - 97 %). f . a 50 ml flask was flame dried and fitted with a magnetic stirrer and a drying tube . dry benzene ( 25 ml ), pyridine ( 0 . 554 g , 3 equivalents ), 4 - dimethylaminopyridine ( dmap , 0 . 10 g , catalyst ) and 2 -( 4 - methylthiophenoxy - 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- 1 - cyclohexanol ( 1 . 755 mmol ) were added and allowed to stir for 5 minutes until all of the added dmap had dissolved . to the solution , 3 , 5 - dinitrobenzoyl chloride ( 1 . 22 g , 3 . 9 equivalents ) was added and the mixture was stirred for 24 hours . the solution was filtered through celite and the solvent was stripped in vacuo . the crude oil was purified by column chromatography with 50 / 50 ethyl acetate / pet ether escalating to 100 % ethyl acetate after 1 column volume . final product 6 , 2 -( 4 - methythiophenoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl ) cyclohexyl - 3 , 5 - dintrobenzoate , was isolated as an orange oil in moderate yields ( 32 - 54 %). the reaction synthesis proceeded as in example 1 until subreaction e . four equivalents of 2 - napthol were added in place of the 4 - methylthiophenol . after subreaction e produced the corresponding alcohol ( subproduct 5 ), 2 -( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7 trioxanonanyl )- 1 - cyclohexanol , subreaction f proceeded as in example 1 and produced 2 -( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- cyclohexyl - 3 , 5 - dintrobenzoate , final product 7 , which was purified and isolated as an orange or yellow oil in moderate yield ( 32 - 54 %). the reaction proceeded as in example 2 for the synthesis of 2 -( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- 1 - cyclohexanol . a 100 ml flask was then flame dried , purged with dry nitrogen and fitted with a magnetic stirrer , condenser and dropping funnel . dry thf ( 25 ml ) was added to the flask and subproduct 5 , 2 -( 2 - napthoxy )- 4 , 5bis ( 1 , 4 , 7 - trioxanonanyl )- 1 - cyclohexanol ( 0 . 400 g , 0 . 797 mmol ), and sodium hydride ( 0 . 0765 g , 2 . 0 equiv ., 50 %, unwashed ) were added and the mixture was stirred for 4 hours . the reaction flask was immersed in a brine ice bath and cooled to - 5 ° c . to the chilled solution , 3 - nitrobenzyl bromide ( 0 . 362 g , 2 . 1 equiv .) dissolved in 25 ml of dry thf , was added over a 4 hour period . the reaction mixture was stirred at 0 ° c . for an additional 4 hours , then allowed to warm to room temperature . the mixture was then warmed and allowed to reflux for 24 hours . the solution was cooled , filtered through a celite pad and the solvent removed in vacuo . the crude product was purified by column chromatography using 50 / 50 ethyl acetate / pet ether ( r f ( prod )= 0 . 41 on tlc ) yielding pure 2 -( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- cyclohexyl - 3 - nitrobenzyl ether , final product 8 , as a yellow oil . the product was a result of the stepwise reaction scheme illustrated in fig2 . the reaction steps proceeded as follows . a . 1 , 4 - cyclohexadiene ( 50 . 0 g , 0 . 626 mol ) was added to a mixture of 225 ml of distilled water and 25 ml of ρ - dioxane . the mixture was stirred at 25 ° c . and n - bromo succinimide ( 108 . 9 g , 0 . 612 mol ) was added slowly over a 1 hour period . the mixture was allowed to stir an additional 3 hours . the reaction mixture was then extracted 3 times with 100 ml portions of chloroform . the combined organic layers were then extracted 3 times with 50 ml portions of saturated aqueous sodium bicarbonate then dried over sodium sulfate and filtered . the solvent was removed in vacuo and the crude bromohydrin was immediately added to 1050 ml of a freshly prepared 1 . 0n sodium hydroxide solution and allowed to stir for 1 hour at 25 ° c . the reaction mixture was extracted three times with 100 ml portions of chloroform and the combined organic layers were dried over sodium sulfate and filtered . the solvent was removed in vacuo giving the crude epoxide which was distilled at 5 mm hg . the fraction collected at 38 °- 40 ° c . ( 58 . 5 g , 97 %) was shown to be [ 4 . 1 . 0 ] bicyclo - 7 - oxo - hept - 3 - ene , subreaction product 9 . b . to 126 ml of a 6n solution of potassium hydroxide was added 15 ml of ρ - dioxane and 123 . 4 g ( 243 . 6 mmol ) of [ 4 . 1 . 0 ] bicyclo - 7 - oxo - hept - 3 - ene . the stirred mixture was allowed to reflux for 24 hours and then cooled to room temperature . 150 ml of brine was added and the mixture was extracted 7 times with 50 ml aliquots of chloroform . the combined organic layers were dried over sodium sulfate and the solvent was removed in vacuo . the resulting oil solidified upon standing giving the crude diol , which was dissolved in hot ethyl acetate , decolorized with activated charcoal and recrystallized from hot 75 % ethyl acetate / 25 % heptane to give subreaction product 10 ; [ 1 ( r , s ), 2 ( r , s )] 4 cyclohexen - 1 , 2 - diol , as white crystals , 15 . 9 g ( 57 . 4 %): mp 97 °- 9 ° c . c . a 500 ml flask was flame dried and fitted with a mechanical stirrer , condenser , and addition funnel . the flask was charged with 125 ml dry thf and [ 1 ( r , s ), 2 ( r , s )] 4 cyclohexen - 1 , 2 - diol ( 4 . 0 g , 35 mmol ) was added and stirred until all of the added solid had dissolved . to the solution , 18 - crown - 6 ( 0 . 200 g ) and sodium hydride ( 6 . 90 g , 2 . 1 equivalents , 50 % washed twice with hexane ) were added and the mixture was stirred for 4 hours at room temperature . bromoacetic acid ( 9 . 75 g , 2 . 0 equivalents , 85 %) was dissolved in 100 ml of dry thf , transferred to the addition funnel and added dropwise to the reaction mixture over a 4 hour period . the dropping funnel was removed and the reaction flask was fitted with a heating mantle . the reaction mixture was warmed and allowed to reflux for 48 hours . the solvent was removed in vacuo and the residue was dissolved in 50 ml of saturated sodium bicarbonate . concentrated hydrochloric acid was added to the solution until acidic to litmus ( caution : gas evolution ) and the acidic aqueous solution was extracted 3 times with ether . the combined organic extracts were dried over magnesium sulfate and the solvent was removed in vacuo . the crude diacid was recrystallized from hot ethyl acetate yielding pure 1 ,( r , s ), 2 ( r , s )- 1 , 2 - bis ( carboxymethoxy )- 4 - cyclohexane , subreaction product 11 , as white crystals ( 27 %). m . p . 87 . 5 °- 90 ° c . d . a 50 ml flask was flame dried and fitted with a magnetic stirrer and drying tube . dry benzene ( 10 ml ), dry thf ( 10 ml ) and 1 ,( r , s ), 2 ( r , s )- 1 , 2 - bis ( carboxymethoxy )- 4 - cyclohexane ( 0 . 900 g , 3 . 91 mmol ) were added to the flask and stirred until all of the added solid had dissolved . thionyl chloride ( 1 . 384 g , 3 . 0 equiv .) was added and the mixture was stirred for 20 hours . the solvent was removed in vacuo and dry benzene ( 25 ml ) was added . the process was repeated two more times , then a final addition of dry benzene ( 20 ml ) was added and the reaction mixture was chilled to 0 ° c . in an ice bath . dipropyl amine ( 2 . 764 g , 7 . 0 equiv .) was added and the solution was stirred for an additional 24 hours . the solvent was removed and the residue was dissolved in 50 ml of chloroform and extracted three times with 1n hcl , three times with saturated aqueous sodium bicarbonate and the layers separated . the organic layer was dried over magnesium sulfate , filtered and the solvent removed in vacuo leaving 1 ( r , s ), 2 ( r , s )- 1 , 2 - bis ( dipropylcarbamoyl ) methoxy - 4 - cyclohexene , subreaction product 12 , ( 0 . 974 g , 63 %) as a yellow oil . e . a dry 100 ml flask was charged with methylene chloride ( 50 ml ) and chilled in an ice bath to 0 ° c . 1 ( r , s ), 2 ( r , s )- 1 , 2 - bis ( dipropylcarbamoyl ) methoxy - 4 - cyclohexene ( 0 . 974 g , 2 . 53 mmol ) and meta - chloroperoxy - benzoic acid ( 1 . 31 g , 3 . 0 equiv ., 85 % ( tech )) were charged to the flask and stirred for 8 hours at 0 ° c . the reaction mixture was allowed to stand at room temperature overnight then the solvent was removed in vacuo with the bath temperature not exceeding 30 ° c . the residue was dissolved in diethyl ether ( 50 ml ) and the solution was extracted three times with 20 % aqueous sodium bisulfite , three times with saturated sodium bicarbonate and once with brine . the organic layer was dried over sodium sulfate , filtered and the solvent removed in vacuo . the epoxide was purified by column chromatography using 90 / 10 ethyl acetate / petroleum ether yielding the product of subreaction e as pure 1 ( r , s ), 2 -( s , r ), 4 ( r , s ), 5 ( r , s )- 4 , 5 bis (( dipropylcarbamoyl )- methoxy - 4 - oxa -[ 4 . 1 . 0 ]- bicycloheptane ( subreaction product 13 ) as a clear oil ( 0 . 48 g , 45 %. f . a 100 ml flask was flame dried , purged with dry nitrogen and fitted with a magnetic stirrer , heating mantle and condenser . dry thf ( 25 ml ), t - butanol ( 25 ml ), potassium t - butoxide ( 0 . 700 g , 2 . 5 equiv .) and 4 - methylthiophenol ( 1 . 0515 g , 3 . 0 equiv .) were added and the mixture was allowed to stir until all of the added solid had dissolved . 1 ,( r , s ), 2 ,( s , r ),- 4 ( r , s ), 4 ( r , s ), 5 ( r , s )- 4 , 5 - bis (( dipropylcarbamoylmethoxy )- 4 - oxa -[ 4 . 1 . 0 ]- bicycloheptane ( 1 . 030 g , 2 . 50 mmol ) was added and the mixture was warmed and allowed to reflux for 72 hours . the reaction vessel was cooled to room temperature and the solvent was removed in vacuo . the residue was dissolved in diethyl ether and extracted 4 times with saturated sodium carbonate and once with brine . the organic layer was dried over sodium sulfate , filtered and the solvent was removed in vacuo . pure product f was obtained by column chromatography of the residue with 100 % ethyl acetate yielding pure 1 ,( r , s ), 2 ( r , s ), 4 ( r , s ), 5 ( r , s )- 4 , 5 - bis ( dipropylcarbamoyl )- methoxy )- 2 -( 4 - methyl thiophenoxy )- cyclohexanol , subreaction product 14 , ( 0 . 423 g , 31 %) as a viscous oil . g . a 50 ml flask was flame dried , fitted with a magnetic stirrer and a drying tube and charged with dry benzene ( 25 ml ). pyridine ( 0 . 242 g , 4 . 0 equiv . ), dimethylaminopyridine ( dmap , 0 . 0050 g , cat ) and 1 ,( r , s ), 2 ( r , s ), 4 ( r , s ), 5 ( r , s )- 4 , 5 - bis ( dipropylcarbamoyl )- methoxy )- 2 -( 4 - methyl thiophenoxy )- cyclohexanol ( 0 . 423 g , 0 . 7663 mmol ) were charged to the flask and allowed to stir until all of the added materials had dissolved . to the mixture , 3 , 5 - dinitrobenzoyl chloride ( 0 . 530 g , 4 . 0 equiv .) was added and the solution was stirred for 72 hours . the solution was filtered and then extracted three times with 1n ( hcl , three times with saturated sodium bicarbonate and once with brine . the solution was dried over sodium sulfate , filtered and the solvent removed in vacuo leaving final product 15 , 1 ( r , s ), 2 ( r , s ),- 4r , s ), 5 ( r , s ), 4 , 5 - bis (( dipropylcarbamoyl )- methoxy )- 2 -( 4 - methylthiophenoxy - cyclohexyhexyl - 3 , 5 - dinitrobenozate as a yellow - orange oil which was further purified by column chromatography with ethyl acetate ( 0 . 545 g , 95 %). complexation of na + 1 , k + 1 , rb + 1 and cs + 1 by : 1 ( s , r ), 2 ( s , r ), 4 ( s , r , 5 ( s , r )- 2 ( 4 - methylthiophenoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- cyclohexyl - 3 , 5 - dinitrobenzoate , 1 ( s , r ), 2 ( s , r ), 4 ( s , r ), 5 ( s , r )- 2 ( 2 - napthoxy )- 4 , 5 - bis -( 1 , 4 , 7 - trioxanonanyl )- cyclohexyl - 3 , 5 - dinitrobenzoate , and 1 ( s , r ), 4 ( s , r ), 5 ( s , r )- 2 ( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanoanyl )- cyclohexyl - 3nitrobenzyl ether a known amount of a charge transfer ionophore was dissolved in a solvent such as methanol and a premeasured amount of solid salt was added to the solution . suitable salts include sodium nitrate , potassium bromate , potassium chloride and bromide , rubidium perchlorate and cesium chloride . the vial was shaken vigorously for about two minutes and the uv - visible absorption spectrum was taken . this was then subtracted from a spectrum of the free ionophore . the effect of the addition of 1 . 0 equivalent of salt to 0 . 0050m solutions of the three ionophores : 1 ( s , r ), 2 ( s , r ), 4 ( s , r ), 5 ( s , r )- 2 ( 4 - methylthiophenoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- cyclohexyl - 3 , 5 - dinitro - benzoate , 1 ( s , r ), 2 ( s , r ), 4 ( s , r ), 5 ( s , r )- 2 ( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7trioxanonanyl )- cyclohexyl - 3 , 5 - dinitrobenzoate , and 1 ( s , r ), 2 ( s , r ), 4 ( s , r ), 5 ( s , r )- 2 ( 2 - napthoxy )- 4 , 5 - bis ( 1 , 4 , 7 - trioxanonanyl )- cyclohexyl - 3nitrobenzyl ether , is plotted as fig5 . complexation of ca + 2 , mg + 2 and sr + 2 by : 1 ( s , r ), 2 ( s , r ), 5 ( s , r )- 4 , 5 - bis (( 4 - dipropylcarbamoyl )- methoxy )- b 2 -( 4 - methylthiophenoxy )- cyclohexyl - 3 , 5 - dintrobenzoate a known amount of 1 ( s , r ), 2 ( s , r ), 5 ( s , r )- 4 , 5 - bis (( 4 - dipropylcarbamoyl )- methoxy )- 2 -( 4 - methylthiophenoxy )- cyclohexyl - 3 , 5 - dintrobenzoate was dissolved in a solvent such as methanol , acetonitrile , or nitromethane . a premeasured amount of solid salt was added to the solution . suitable salts include magnesium nitrate hexahydrate , calcium nitrate tetrahydrate and strontium nitrate . the vial was shaken vigorously for about two minutes and the uv - visible absorption spectrum was taken . this was then subtracted from a spectrum of the free ionophore . the effect of salt addition to a 0 . 0050m solution of 1 ( s , r ), 2 ( s , r ), 5 ( s , r )- 4 , 5 - bis (( 4 - dipropylcarbamoyl ) - methoxy )- 2 -( 4 - methylthiophenoxy )- cyclohexyl - 3 , 5 - dintrobenzoate methanol is summarized on fig3 and 4 . as can be appreciated from fig1 and 2 and the above examples , the preparation of desired electron acceptor and / or donor groups can be inserted as various reactants to make them present in the final product . the electron donor and acceptor reactants are preferably from 6 to 20 carbon atoms . examples of suitable electron acceptor / donors are listed below with reference to a desirable reactant in fig1 - 2 : ______________________________________desired reactants figure #, for above electron acceptors product # ______________________________________2 -( 4 - methylethiophenoxy - 1 , 54 , 5 - bis -( 1 , 4 , 7 - trioxanonanyl )- 2 - cyclohexanol2 -( 2 - napthoxy )- 4 , 5 - bis -( 1 , 4 , 7 - 1 , 5trioxanonanyl )- 1 - cyclohexanol4 , 5 - bis ( dipropylcarbamoyl )- 2 , 14methoxy )- 2 -( 4 - methylthiophenoxy )- cyclohexanol______________________________________ ______________________________________desired reactants figure #, for above electron donors product # ______________________________________1 ( r , s ), 2 ( s , r ), 4 ( s , r ) 1 , 45 ( s , r )- 4 , 5 - bis ( 1 , 4 , 7 - trioxonanyl )- cyclohex - 1 - eneoxide1 ( r , s ), 2 ( s , r ), 4 ( r , s ), 2 , 135 ( r , s )- 4 , 5 - bis ( dipropylcaramoyl )- methoxy )- 4 - oxa [ 4 . 1 : 0 ] bicycloheptane______________________________________ it is contemplated that the invention can be utilized in the following manner to quantitatively determine the concentration of ca + 2 in a sample of human or mammalian body fluid . an organic extraction , using a suitable , non - h 2 o miscible organic solvent such as chloroform , methylene chloride , or ether containing a tetra substituted cyclohexane composition , will be performed on a sample of body fluid . after separation , the organic mixture will be subjected to a uv - spectrophotometer . known amounts of ca + 2 will be added to sample aliquots of the organic mixture . a plot of absorbance versus [ ca + 2 ] will allow the determination of the [ ca + 2 ] of the body fluid via interpolation or extrapolation . while the forms of the invention herein disclosed constitute presently preferred embodiments , many others are possible . it is not intended herein to mention all of the possible equivalent forms or ramifications of the invention . it is understood that the terms used herein are merely descriptive rather than limiting , and that various changes may be made without departing from the spirit or scope of the invention .