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diff --git a/macros/latex209/contrib/chemtex/chap3a.tex b/macros/latex209/contrib/chemtex/chap3a.tex new file mode 100644 index 0000000000..8429a50913 --- /dev/null +++ b/macros/latex209/contrib/chemtex/chap3a.tex @@ -0,0 +1,581 @@ +\chapter{\TeX/\LaTeX\ code for components of organic chemical structure + diagrams}\label{ch:txltx} +\section{Conventions for drawing the diagrams}\label{sc:convntns} + The chemical structure of a molecule is defined by the spatial + arrangement of the atoms and the bonding between them. + Chemists use several standard methods for representing the + structures two-dimensionally by diagrams called structural + formulas; and this thesis will develop mechanisms for printing + such diagrams using the \TeX/\LaTeX\ system. + + A very common structure representation, sometimes called a + dash structural formula, uses the element symbols for the + atoms and a dash for each covalent bond in the compound. + Thus the dash represents the pair of shared electrons that + constitutes the bond. Two dashes ($=$) represent a double + bond and three dashes ($\equiv $) a triple bond. --- + It is usually neither necessary nor practical to represent + each bond in a molecule explicitly by a dash. + Some molecules and some bonds are so common that a complete + dash formula would not be used except at a very introductory + level of presenting chemical information. + A condensed structural formula is one alternative. It does + not contain dashes but uses the convention that atoms + bonded to a carbon are written immediately after that + carbon and otherwise atoms are written from left to right + in the order in which they occur in the real structure. + The following two structural formulas are a dash formula + and a condensed formula, respectively, for the same + compound, ethanol. + \[ \parbox{4.5cm} { + \begin{picture}(400,900)(0,-110) + \put(0,0) {\cbranch{H}{S}{H}{S}{C}{S}{}{S}{H} } + \put(240,0) {\cbranch{H}{S}{}{Q}{C}{S}{O---H}{S}{H} } + \end{picture} } + \hspace{1.5cm} + {\rm CH_{3}CH_{2}OH} \] + Multiple bonds are usually not implied unless a very common + group, such as the cyano group, is shown. It can be found + as $-$C$\equiv $N or simply as $-$CN. + + Another alternative to a complete dash formula is a diagram + where the symbols for carbon and for hydrogen on carbon are + not shown. Each corner and each open-ended bond in these + diagrams implies a carbon atom with as many hydrogen + atoms bonded to it as there are free valences. This + representation is the customary one for ring structures + (structures with a closed chain of atoms). Thus, the + following two diagrams both represent the compound + cyclopropane. + \[ \hetthree{Q}{H}{H}{H}{H}{S}{S}{C} + \hspace{3cm} \yi=330 + \threering{Q}{Q}{Q}{Q}{Q}{Q}{Q}{Q}{Q} \] + + \reinit + The three different kinds of structure representation can + be combined in one diagram, such that in part of the + diagram all bonds are represented by dashes and all + atoms by an element symbol, in another part a condensed + structural formula fragment is used, and in still + another part a cyclic fragment with implied carbon + and hydrogen atoms occurs. + + The rest of this chapter describes how \LaTeX\ can be used + to position and typeset the bond lines and condensed + formula strings that are the components of structure + diagrams. + + It should be mentioned that there are no binding rules + for many aspects of the two-dimensional representations + of a chemical structure. Structures and fragments of + structures can be oriented in different ways depending + on the availability of space, the emphasis given to + a certain part of a structure, or the spatial + relationship of the parts to each other. + Thus, a cyclopropane ring can be represented in various + orientations, $\bigtriangleup $, $\bigtriangledown $, + and others. Also, the angles between + the bond lines can be different in different representations + of one and the same compound. Since most molecules do not + have all their atoms lying in one plane it would not + even be possible to reproduce all bond angles in a + two-dimensional representation. The structures shown in + this thesis adopt the orientations and bond angles + found to prevail in Solomons' textbook (Solomons 84), + the organic chemistry text used for several years at + the University of Tennessee. + + There are some methods to indicate the real, + three-dimensional structure (the stereochemistry) + of a molecule in the two-dimensional representation: + A dashed line and a wedge instead of a full bond + line mean that the real bond extends below or + above the plane, respectively. + +\section{Bond line drawing and positioning} +\subsection{Review of \TeX/\LaTeX\ facilities for line-drawing} +\label{sc:review} + The easiest way to produce horizontal and vertical lines representing + chemical bonds is by the use of keyboard characters and simple control + sequences provided by \TeX. By typing one, two, or three hyphens, + a normal hyphen, a medium dash designed for number ranges, and a + punctuation dash are produced, - -- ---, respectively. When a hyphen + is typed in \TeX's math mode, it is interpreted as a minus sign and + the spacing around it will be different from text mode. --- + The equal sign can represent a double bond for chemistry typesetting. + It can be typed in text mode and in math mode, again resulting in + different spacing around the symbol. --- The control sequence + \verb+\equiv+ can be used as a triple bond ($\equiv $). It has to + be typed in math mode. + + Vertical lines are available through the keyboard character or the + control sequences \verb+\vert+ and \verb+\mid+, all three to be + entered in math mode. + A double vertical bar is produced by \verb+\|+ or \verb+\Vert+, + again both in math mode. + + The spacing around all these symbols can be controlled by adding + extra (positive or negative) space with the horizontal spacing + commands. The symbols, just as any other part of a line, can also + be raised or lowered respective to the normal baseline. The length + and height of the symbols however depend on the font currently + in use. + + Where control of length and height of the bond lines is needed, + \TeX's or \LaTeX's command sequences for printing horizontal and + vertical ``rules'' can be used. The systems recognize several + length units, including the inch, centimeter, millimeter, and + printer point (Knuth 84, p. 57). One printer point (pt), an often + used unit in typesetting, measures about 0.35 mm. --- \LaTeX's + rule-printing command has the format + $$\hbox{\verb+\rule[raise-length]{width}{height}+}$$ + Thus it can be used to produce horizontal and vertical rules. + Using the \verb+\rule+ command one can also print multiple + bond lines of user-controlled length, e.~g. $\dbond{16}{10} $, + $\tbond{16}{11} $, with the short control sequences \verb+\dbond+ + and \verb+\tbond+ defined in this thesis. The vertical spacing + between the bonds depends on the current line spacing in the + document and may have to be adjusted. The control sequences + are set up for math mode. + + When bond lines other than horizontal and vertical ones are to + be printed, and when a coordinate system is needed to control + placement of structure components relative to one another, + \LaTeX's picture environment (Lamport~86, pp.~101--111) is a + necessity. + + A picture environment uses length units which are dimensionless + and have to be defined by the user before entering the + environment. This is done by the \verb+\setlength+ command. + In this study, \verb+\setlength{\unitlength}{0.1pt}+ + is the definition used for most diagrams. Such a small + unitlength was chosen to have fine control over the appearance + of the diagram. + + The picture environment starts with the statement + $$\hbox{\verb+\begin{picture}(width,height)+}$$ + where picture width and height reserve space on the page + and are specified in terms of unitlengths. Optionally, one + can include the coordinates of the lower left corner of the + picture: + $$\hbox{\verb+\begin{picture}(width,height)(x+$_i$\verb+,y+$_i$\verb+)+}$$ + The default value for these coordinates is (0,0). + Objects are placed into the picture with the \verb+\put+ + command with their reference point at the coordinates (x,y): + \verb+\put(x,y){picture object}+. + + The picture objects of most interest to this study are + straight lines. They are drawn by the \verb+\line+ + command: + $$\hbox{\verb+\line(x+$_s$\verb+,y+$_s$\verb+){length}+}$$ + where the coordinate pair specifies the slope of the line, + and the nonnegative value of length specifies the length + of the projection of the line on the x-axis for all + nonvertical lines, and the length of the line for vertical + lines. The reference point of a line is one of its ends. + Thus the statement + $$\hbox + {\verb+\put(x,y)+ + \verb+{\line(x+$_s$\verb+,y+$_s$\verb+){len}}+} + $$ + draws a line that begins at (x,y), has a slope of ${\rm y_s\mbox{/}x_s}$, + and extends for length len as explained above. + + Only a limited number of slopes is available through the line + fonts in \LaTeX. The possible values for ${\rm x_s}$ and ${\rm y_s}$ are + integers between $-6$ and $+6$, inclusive. These values translate + into 25 different absolute angle values, which are listed + in Appendix~\ref{ap:slopes}. + +\subsection{Bonds in structural formulas written on one line} +\label{sc:onelinebonds} + The application of some of the bond-drawing mechanisms for this + simplest type of structural diagrams is illustrated in + Figure~\ref{fg:oneline}. + \begin{figure}\centering + \begin{picture}(900,700) + \put(0,600) {a \ $CH\equiv C-CH=CH_{2}$} + \put(0,350) {b \ $CH$\raise.1ex\hbox{$\equiv$}$C-CH=CH_{2}$} + \put(0,100) {c \ $CH\tbond{14}{20} C\sbond{14} + CH\dbond{14}{19} CH_{2}$} + \end{picture} + \caption{One-line structural formulas} + \label{fg:oneline} + \end{figure} + + For Figure~\ref{fg:oneline}a only keyboard characters and the \TeX\ + command \verb+\equiv+ were used to produce the bonds. + Figure~\ref{fg:oneline}b + shows a slight improvement through raising the triple bond. + Figure~\ref{fg:oneline}c was printed using the \verb+\sbond+, + \verb+\dbond+, and \verb+\tbond+ command sequences from + this thesis, choosing a length of 14pt for the bonds. + It can be seen that each of the formulas in Figure~\ref{fg:oneline} + is a + creditable representation of the structure. Depending on the + design of the page, the reason for displaying the structure + at a particular place, and the emphasis put on features of the + structure in the text, one would choose shorter or longer + bonds and take more or less trouble to produce the structure. + + The picture environment is not needed for one-line structural + formulas, unless one of these formulas has to be attached to + another structural fragment, as in Figure~\ref{fg:picline} + Then the + coordinate system of the picture environment makes it + possible to fit the two fragments together. + \begin{figure} + \hspace{5cm} + \parbox{70 pt} { + \begin{picture}(400,200) + \put(-155,0) {$CH_{3}-CH-CH_{2}-CH_{2}-CH_{2}-CH_{3}$} + \end{picture} } + \hspace{5cm} \yi=200 \pht=600 + \sixring{Q}{Q}{Q}{Q}{Q}{}{D}{D}{D} \\ + \caption{One-line structure in picture environment} + \label{fg:picline} + \end{figure} +\subsection{Bonds in acyclic structures with vertical branches} + Structure diagrams with vertical, single- or double-bonded, branches, + going up or down, are frequently seen. Several experiments with \TeX\ + and \LaTeX\ were made to see how this type of structure can be + handled. One method is to align the vertical bonds by using the + mechanisms for tabbing or for printing tables and matrices. + Here a structure such as the one shown in Figure~\ref{fg:vertbranch} + is treated + as a set of columns as indicated by the vertical dividing lines + drawn into the second version of this structure in + Figure~\ref{fg:vertbranch}. + + \begin{figure} + \hspace{1cm} + \begin{minipage}{180pt} + \begin{tabbing} + $CH_{3}CH_{2}$\= $CH$\= $CHCH_{2}$\= $CHCH_{2}CH_{3}$\+ \kill + $Br$\> \> $CH_{3}$ \\ + \hspace{2pt}$\vert $\> \> \hspace{2pt}$\vert $ \- \\ + $CH_{3}CH_{2}$\> $CH$\> $CHCH_{2}$\> $CHCH_{2}CH_{3}$\+ \+ \\ + \hspace{2pt} $\vert $ \\ + $CH_{2}CH_{3}$ + \end{tabbing} + \end{minipage} + \hspace{2.5cm} + \begin{minipage}{180pt} + \begin{tabbing} + $CH_{3}CH_{2}$\= $\vert CH$\= $\vert CHCH_{2}$\= $\vert CHCH_{2}CH_{3}$ + \+ \kill + $\vert Br$\> $\vert $ \> $\vert CH_{3}$ + \\ + $\vert $\hspace{2pt}$\vert $\> $\vert $ \> $\vert $\hspace{2pt} + $\vert $ \- \\ + $CH_{3}CH_{2}$\> $\vert CH$ \> $\vert CHCH_{2}$\> $\vert CHCH_{2}CH_{3}$ + \+ \\ + $\vert $\> $\vert $\hspace{2pt}$\vert $ \> $\vert $ + \\ + $\vert $\> $\vert CH_{2}CH_{3}$ + \end{tabbing} + \end{minipage} + \caption{Vertical branches}\label{fg:vertbranch} + \end{figure} + + The structure diagram in Figure~\ref{fg:vertbranch} + uses \verb+\vert+ for the vertical + bonds and \LaTeX's tabbing environment for the alignment. One can also + use ``rules'' as the vertical bonds in order to give the horizontal + and vertical bonds the same lengths. Furthermore, vertical bonds can + also be double bonds. The following examples illustrate these features. + $$ + \tbranch{O}{D}{H_{2}N-}{C-NH_{2}}{}{}{1} \hspace{2cm} + \tbranch{}{}{CH_{3}-CH_{2}-}{C-CH_{3}}{D}{NH}{1} \hspace{2cm} + \tbranch{}{}{H-}{C=\ }{S}{Br}{1}\tbranch{}{}{}{C-H}{S}{Br}{1} + $$ + Similar structures were also generated with \TeX's \verb+\halign+ + mechanism which forms templates for the columns rather than setting + tab stops. For the purpose of printing the structure diagrams, no + clearcut advantage was seen in one or the other method of + alignment. In each case the vertical spacing depends on the line + spacing in the document. + + The alternative method of producing these structures is the use + of the picture environment. It provides better control over + horizontal and vertical spacing and over bond lengths. Also, + as illustrated in Section~\ref{sc:onelinebonds}, + using a picture environment makes + it possible to attach one structural fragment to another at + a specific place. Thus, although the picture environment is not + necessary for drawing structures with vertical branches, it + has several advantages, and writing \LaTeX\ code for this + implementation is not more difficult than writing the code + for the tabbing method of alignment. + +\subsection{Bonds in Structures Containing Slanted Bond Lines} + Structure diagrams with slanted bond lines are frequently used for + acyclic compounds and have to be used to depict almost all cyclic + structures. Two examples are shown here: + $$ \cdown{$CH_{3}$}{S}{$N^{+}$}{D}{$O$}{S}{$O^{-}$} + \hspace{3cm} \sixring{$COOH$}{$OCOCH_{3}$}{Q}{Q}{Q}{Q}{S}{S}{C} $$ + + In developing diagrams for such structures in this thesis the + conventions described in Section~\ref{sc:convntns} are followed. + Thus the symbol for carbon is not + printed for the carbons that are ring members, but it is usually + printed in acyclic structures, unless the acyclic structure fragment + is a long chain, or space for the diagram is limited. + + The picture environment is always needed for slanted lines. It was + explained in Section~\ref{sc:review} that \LaTeX\ can draw lines + only with a finite number of slopes. This is not a severe limitation + for creating the structure diagrams, since the conventions for + structure representation allow variations in the angles. + The representation does not have to reflect the true + atomic coordinates. In fact many chemistry publications contain + structure diagrams with angles significantly deviating from the real + bond angles, even where those could have been used easily. Thus, + Solomons' text (Solomons~84) + shows the carboxylic acid group often in this form + \pht=600 + \[ \cright{}{S}{C}{D}{O}{S}{OH} \] + \pht=900 + with an angle of about $90\circ$ between the OH and doublebonded O, + whereas the true angle is close to $120\circ$. --- The angles used + in this thesis for the regular hexagon of the sixring deviate by + % \parbox{4mm}{+\vspace{-18pt}\\ $-$}~$1^0$ from $120^0$ + $\pm 1^\circ$ from $120^\circ$ + because of \LaTeX's limited + number of slopes. This difference is not big enough to be + detected as a flaw. + + To write the \LaTeX\ statement for a slanted bond line, one chooses the + origin and the slope and then uses trigonometric functions to calculate + the \LaTeX\ ``length'' of the line for the desired real length. Once the + \LaTeX\ length is determined, the coordinates of the end point of the + line can be calculated in case the end point is needed as the origin + of a connecting line. --- The origin and length of slanted double + bonds were also calculated with standard methods from trigonometry. + As an example, Figure~\ref{fg:calcpos} + shows how coordinates of the origin were + calculated for the inside part of a ring double bond that is at a + distance d from the outside bond. + + \setlength{\unitlength}{1pt} + + \begin{figure} + \begin{picture}(300,250)(0,-100) + \thicklines + \put(0,0) {\line(5,3) {120}} + \put(120,72) {\line(5,-3) {120}} + \put(240,0) {\line(0,-1) {100}} + \put(215,-6) {\line(-5,3) {88}} + \thinlines + \put(120,72) {\circle*{4}} + \put(125,72) {($x$,$y$)} + \put(127,47) {\circle*{4}} + \put(132,47) {($x_d$,$y_d$)} + \put(120,72) {\line(0,-1) {16}} + \put(120,72) {\line(-3,-5){9}} + \put(111,56) {\line(1,0) {16}} + \put(127,56) {\line(0,-1) {9}} + \put(111,56) {\line(5,-3) {16}} + \put(111,62) {\scriptsize d} + \put(116,46) {\scriptsize d} + \put(112,17) {{\small $\theta =30^{0}$}} + \put(114,28) {\vector(0,1){27}} + \put(270,35) {$x_{d}=x-d\sin ${\small $\theta $}$+d\cos ${\small $\theta $}} + \put(270,5) {$y_{d}=y-d\sin ${\small $\theta $}$-d\cos ${\small $\theta $}} + \end{picture} + \caption{Calculating position and length of double bond.} +\label{fg:calcpos} + \end{figure} + + \reinit + + The \LaTeX\ command \verb+\multiput+ is similar to \verb+\put+ and provides + a shortcut for the coding of structures where several bond lines of the + same slope and length occur at regular intervals. Multiput has the + format +$$\hbox {\verb+multiput(x,y)(x+$\Delta$\verb+,+$\Delta$\verb+y){n}+ + \verb+{object}+}$$ + where n is the number of objects, {\em e.g.,\/} + lines. A structure diagram + for which several \verb+\multiput+ statements are appropriate is + the structure of vitamin~A shown in Figure~\ref{fg:multidiag} + + \begin{figure} + \hspace{2cm} + \parbox{5cm} { + \begin{picture}(900,900)(-300,-300) + \put(342,200) {\line(0,-1) {200}} + \put(342,0) {\line(-5,-3) {171}} + \put(171,-103) {\line(-5,3) {171}} + \put(0,0) {\line(0,1) {200}} + \put(0,200) {\line(5,3) {171}} + \put(171,303) {\line(5,-3) {171}} + \put(322,180) {\line(0,-1) {160}} + \put(342,0) {\line(5,-3) {128}} + \put(171,303) {\line(5,3) {128}} + \put(171,303) {\line(-5,3) {128}} + \multiput(342,200)(342,0){5}{\line(5,3){171}} + \multiput(513,303)(342,0){4}{\line(5,-3){171}} + \multiput(527,270)(342,0){4}{\line(5,-3){135}} + \multiput(855,303)(684,0){2}{\line(0,1){160}} + \put(1881,275){=O} + \end{picture} } + \caption{Diagram using $\backslash $multiput} +\label{fg:multidiag} + \end{figure} + + The size of objects in a picture environment can be scaled in a simple + way by changing the unitlength. Figure~\ref{fg:scaling} + illustrates scaling and + two problems associated with it. Changing the unitlength changes the + length of the lines only, not the width of the lines or the size of + text characters. Thus ``it does not provide true magnification and + reduction'' (Lamport~86, p.~102). However, the size of the text + characters can be varied separately, as will be discussed in the + next section of this chapter. + \begin{figure} + \pht=750\centering + \setlength{\unitlength}{.07pt} + \sixring{$OH$}{Q}{Q}{Q}{Q}{$Br$}{S}{D}{S} + \hspace{1.5cm} + \setlength{\unitlength}{0.08pt} + \sixring{$OH$}{Q}{Q}{Q}{Q}{$Br$}{S}{D}{S} + \hspace{1.5cm} \yi=150 + \setlength{\unitlength}{0.15pt} + \sixring{$OH$}{Q}{Q}{Q}{Q}{$Br$}{S}{D}{S} + \caption{Scaling (unitlength=0.07pt, 0.08pt, 0.15pt)} + \label{fg:scaling} + \end{figure} + + The smallest diagram in Figure~\ref{fg:scaling} + illustrates a limitation that + is unfortunate for the printing of structure diagrams. The shortest + slanted line that can be printed by \LaTeX's line fonts is + one with an x-axis projection of about~3.6mm. + If a shorter slanted line is requested, \LaTeX\ just prints + nothing. A chemist would occasionally want to draw shorter lines, + especially for the purpose of generating dashed lines indicating + stereochemical features. + +\section{Atomic symbols and condensed structural fragments} +\label{sc:fragments} + Special considerations for the printing of condensed structural + fragments are required since many of them contain subscripts. + \TeX\ considers the printing of subscripts a part of mathematics + typesetting which has to be done in the special math mode. + As it is known, typesetting of mathematics + documents is one of the strong points of \TeX; the fonts of type + for the math mode are designed to agree with all conventions + of high quality mathematics publishing. Each typestyle in math + mode consists of a family of three fonts (Knuth~84, p.~153), + a textfont for normal symbols, a scriptfont for first-level + sub- and superscripts, and a scriptscriptfont for higher-level + sub- and superscripts. When structural fragments such as + ${\rm C_{2}H_{5}}$ are typeset, the textfont is used + for the C and the~H. + + As \TeX\ enters math mode it selects \verb+\textfont1+ as the textfont + unless otherwise instructed. + \verb+\textfont1+ is defined by the \TeX\ + macros as math italic, a typestyle that prints letters (not + numbers) similar to the italic style, but with certain + features adapted for mathematics typesetting. The italic + style letters, lower and upper case, are the ones commonly + seen in typeset mathematical formulas. Chemical formulas + on the other hand are not usually printed with slanted + letters. In this thesis, two methods were employed + to produce chemistry-style letters in \TeX's math mode which + has to be used because of the presence of subscripts. + + For a document that contains many chemical formulas it is + convenient to redefine + \verb+\textfont1+ at the beginning of the + \TeX\ input file. The statement \verb+\textfont1=\tenrm+ + was used at the beginning of the input file that produced this + document and causes \TeX\ + to select the roman font as the textfont in math mode. + The roman typestyle is the one normally used by \TeX\ + outside of math mode and it is the style in which this + thesis is printed. The ten point size, which is slightly + smaller than the eleven point size of the text in this document, + was chosen because it appears to look better for the + chemical formulas which consist largely of capital letters. + When different typesizes are used in this way, all the + atomic symbols and formulas in any one structure, even + those without subscripts, have to be printed in math mode + so that they all have the same size. It could be a + problem with this method of selecting the roman font for + math mode that the lowercase Greek letters (and some other + symbols used in mathematics) are not available in this + font. To print these one can temporarily redefine + textfont1 to math italic with the statement + \verb+\textfont1=\tenmi+. One can also switch to + a math font different from the default \verb/\textfont1/. + Using one of \LaTeX's font definitions, \verb+\small+, + a statement \{\verb+\small$\theta$+\} will + print the Greek letter. + + Another method for avoiding the math italic style for letters + in chemical formulas is to select the roman style in each + individual instance where a formula has to be printed in + math mode. A statement such as \verb+${\rm C_2H_5}$+ + produces ${\rm C_{2}H_{5}}$ at the size of type currently used + in the document. When the typestyle is thus selected within + math mode, enclosed by dollar signs, \TeX\ changes the style + of the letters of the alphabet only; the lowercase Greek + letters and math symbols remain available. + + The size of the letters in chemical formulas can be changed + with the ten size declarations provided by \LaTeX\ (Lamport~86, + p.~200) or with \TeX's declarations. (Some of \TeX's declarations + are not defined in \LaTeX\ (Lamport~86, p.~205)). The size + declaration has to be written outside of math mode. + One place in chemistry typesetting where a + smaller typesize is desirable is the writing on reaction + arrows. The size in the following example is scriptsize: + $$ + \advance \yi by 100 + HC\equiv CH + H_{2}O + \parbox{92pt} {\cto{Hg^{++}}{18\%\ H_{2}SO_{4},\ 90^\circ}{14}} + CH_{3}-CHO $$ + + Finally, condensed structural formulas sometimes have to be + right-justified to be attached to the main structural diagram. + Figure~\ref{fg:rightjus} + illustrates this for the positioning of the + substituent in the 4-position of the pyrazole ring. \LaTeX\ + makes this positioning convenient with the \verb+\makebox+ + command, especially in the picture environment where the command + has the format + $$\hbox{\verb+\makebox(width,height)[alignment]{content}+}$$ + (Lamport~86, p.~104). The one-line piece of text that constitutes + the content of the (imaginary) box can be aligned with the + top, bottom, left side, or right side of the box. + \begin{figure}\centering + \parbox{\xbox pt} { + \begin{picture}(\pw,\pht)(-\xi,-\yi) + \put(200,-84) {\line(5,3) {110}} % bond 1,2 + \put(342,200) {\line(0,-1) {140}} % bond 3,2 + \put(342,200) {\line(-1,0) {342}} % bond 3,4 + \put(0,200) {\line(0,-1) {200}} % bond 4,5 + \put(0,0) {\line(5,-3) {140}} % bond 5,1 + \put(135,-130) {$N$} % N-1 in ring + \put(310,-30) {$N$} % N-2 in ring + \put(171,-137) {\line(0,-1) {83}} % subst. on + \put(150,-283) {$C_{6}H_{5}$} % on N-1 + \put(370,-17) {\line(5,-3) {100}} % subst. on + \put(475,-100) {$C_{6}H_{5}$} % N-2 + \put(335,211) {\line(5,3) {128}} % outside + \put(349,189) {\line(5,3) {128}} % double O + \put(475,250) {$O$} % on C-3 + \put(0,200) {\line(-5,3) {128}} % single subst. + \put(-430,234) {\makebox(300,87)[r]{$CH_{3}COCH_{2}CH_{2}$}} + \put(-7,11) {\line(-5,-3){128}} % outside + \put(7,-11) {\line(-5,-3){128}} % double O + \put(-200,-130){$O$} % on C-5 + \end{picture} } % end pyrazole macro + \caption{Right-justification of substituent formula} + \label{fg:rightjus} + \end{figure} + + |