Catalysts of Diels-Alder reactions, methods and catalysts therefor

A catalyst molecule comprising an antibody combining site that catalyzes the reaction of a cyclic dienophile molecule with a cyclic diene molecule to form a Diels-Alder [4+2] cycloaddition/fragmentation cyclic reaction product that contains a five- or six-membered ring formed by said reaction and that includes at least two endocyclic conjugated double bonds, said dienophile molecule and cyclic diene molecule forming a reactive intermediate upon cycloaddition and prior to fragmentation,

• said dienophile molecule containing a reactive multiple bond and including a moiety that is electron-withdrawing relative to hydrogen located at a position alpha to said reactive multiple bond,
• said conjugate diene molecule having a structure that includes a five- or six-membered ring having a fugitive leaving group that is substantially stable when present in said cyclic conjugated diene and forms a gaseous compound in forming said cyclic reaction product,
• said catalyst molecule immunoreacting with an antigen that is an analog to a transition state leading to the formation of the reactive intermediate, said antigen being isologous to the reactive intermediate and having a structure that (i) includes a [2.2.1] or [2.2.2] bicyclic ring system absent from the reaction product (ii) contains at least one endocyclic double bond fewer in said bicyclic ring system than the number of endocyclic double bonds present in the reaction product, and (iii) contains a group or moiety that is isostructural to the fugitive leaving group and is substantially less reactive in the antigen than is the fugitive leaving group in the reactive intermediate.

A method of forming a cyclic reaction product having a five- or six-membered ring that includes at least two endocyclic conjugated double bonds in a Diels-Alder [4+2] cycloaddition/fragmentation reaction that proceeds though a reactive intermediate comprising the steps of:

• (a) admixing a dienophile molecule having a reactive multiple bond and cyclic conjugated diene molecule having a structure that includes a fugitive leaving group within a five- or six-membered ring with a catalyst molecule in a liquid composition to form a reaction mixture,
• said fugitive leaving group being substantially stable when present in said cyclic conjugated diene and being expelled from said reactive intermediate as a molecular entity to form said cyclic reaction product,
• said catalyst molecule comprising a monoclonal antibody combining site-containing molecule that catalyzes said reaction and immunoreacts with an antigen that is an analog to a transition state leading to the formation of the reactive intermediate,
• said antigen being isologous to the reactive intermediate and having a structure that (i) includes a [2.2.1] or [2.2.2] bicyclic ring system absent from the reaction product, (ii) contains at least one endocyclic double bond per molecule fewer in said bicyclic ring system than the number of endocyclic double bonds present in the reaction product, and (iii) contains a group or moiety that is isostructural to the fugitive leaving group and is substantially less reactive in the antigen than is the fugitive leaving group in the reactive intermediate;
• and
• (b) maintaining said reaction mixture for a time period sufficient for the reaction product to form.

A method of forming a cyclic reaction product that contains a five- or six-membered ring having at least two conjugated endocyclic double bonds in a Diels-Alder [4+2] cycloaddition/fragmentation reaction that proceeds through a reactive intermediate comprising the steps of:

• (a) admixing a cyclic dienophile molecule and a cyclic conjugated diene molecule with a catalyst molecule in an aqueous liquid composition to form a reaction mixture,
• said cyclic dienophile molecule including a double bond that reacts with the two double bonds of said cyclic conjugated diene,
• said cyclic conjugated diene including a fugitive leaving group in a five- or six-membered ring, said fugitive leaving group being substantially stable when present in said cyclic conjugated diene and being expelled from said reactive intermediate as a molecular entity to form said cyclic reaction product,
• said catalyst molecule catalyzing the formation of said cyclic reaction product from said cyclic dienophile and said cyclic conjugated diene and comprising a monoclonal antibody combining site-containing molecule that immunoreacts with an antigen that is an analog to a transition state leading to the formation of the reactive intermediate,
• said antigen being isologous to the reactive intermediate and having a structure that (i) includes a [2.2.1] or [2.2.2] bicyclic ring system absent from the reaction product, (ii) contains at least one endocyclic double bond per molecule fewer in said bicyclic ring system than the number of endocyclic double bonds present in the reaction product, and (iii) contains a group or moiety that is isostructural to the fugitive leaving group and is substantially less reactive in the antigen than is the fugitive leaving group in the reactive intermediate;
• and
• (b) maintaining said reaction mixture under biological conditions for a time period sufficient for the reaction product to form.

A method of preparing a monoclonal antibody combining site-containing molecule capable of catalyzing the formation of a reaction product containing a five- or six-membered ring and at least two endocyclic double bonds in a Diels-Alder [4+2] cycloaddition/fragmentation reaction that proceeds through a reactive intermediate comprising the steps of:

• (a) immunizing an animal host with an immunogen that is relatively non-reactive in the catalyzed reaction,
• said immunogen having a structure that is isologous to the structure of a transition state leading to formation of a Diels-Alder [4+2] cycloadditon reactive intermediate product formed by reaction of a dienophile molecule containing a reactive multiple bond and a cyclic conjugated diene having a fugitive leaving group in a five- or six-membered ring, and which cycloaddition intermediate product is a reactive intermediate in the formation of said reaction product, said fugitive leaving group being substantially stable when present in said cyclic conjugated diene and being expelled from said reactive intermediate as a molecular entity in forming said cyclic reaction product,
• said immunogen having a structure that (i) includes a [2.2.1] or [2.2.2] bicyclic ring structure absent from the reaction product, (ii) contains at least one endocyclic double bond per molecule fewer in said bicyclic ring system than the number of endocyclic double bonds present in the reaction product, and (iii) contains a group or moiety that is isostructural to the fugitive leaving group and is substantially less reactive in the immunogen than is the fugitive leaving group in the reactive intermediate;
• (b) forming hybridoma cells with antibody-secreting cells from an immunized animal host that secretes antibodies that immunoreact with said immunogen;
• and
• (c) clonging and culturing the hybridoma cells that secrete monoclonal antibodies that immunoreact with said immunogen.

A method of forming a bicyclic reaction product having a six-membered ring that includes two endocyclic conjugated double bonds in a Diels-Alder [4+2] cycloaddition/fragmentation reaction that proceeds through a reactive intermediate having [2.2.1] bicyclic ring that includes an SO.sub.2 group that is expelled in forming the bicyclic reaction product comprising the steps of:

• (a) admixing a dienophile molecule containing a reactive double bond and a halogenated thiophene 1,1-dioxide as diene with a catalyst molecule in a liquid composition to form a reaction mixture,
• said catalyst molecule comprising a monoclonal antibody combining site-containing molecule that catalyzes said reaction and immunoreacts with an antigen that is an analog to a transition state for formation of the reactive intermediate, is isologous to the reactive intermediate, and has a structure that (i) includes a [2.2.1] bicyclic ring system absent from the reaction product, (ii) contains one endocyclic double bond fewer in said [2.2.1] bicyclic ring system than the number of endocyclic double bonds present in the reaction product, and (iii) contains a CCl.sub.2 group in the position occupied by said SO.sub.2 group of the reactive intermediate;
• and
• (b) maintaining said reaction mixture for a time period sufficient for the reaction product to form.