Вот выдержка из тех же авторов.
The term "substituents" refers to a group "substituted" on an alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heterocyclyl, heteroaryl, acyl, amino group at any atom of that group.
Следующее предложение:
Suitable substituents include, without limitation, halo, hydroxy, oxo, nitro, haloalkyl, alkyl, alkenyl, alkynyl, alkaryl, aryl, aralkyl, alkoxy, aryloxy, amino, acylamino, alkylcarbanoyl, arylcarbanoyl, aminoalkyl, alkoxycarbonyl, carboxy, hydroxyalkyl, alkylthio, CF3,... cyano or ureido. In some embodiments, substituent can itself be optionally substituted. In some cases, two substituents, together with the carbons to which they are attached to can form a ring. http://www.faqs.org/patents/app/20100130574

Очевидно, что в этом списке такие заместители, как halo, hydroxy, oxo, nitro никак не могут быть образованы замещением одного атома какой-либо группы на "alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heterocyclyl, heteroaryl, acyl, amino".

Т.е. автор под "Substituents" имеет в виду заместители в обычном смысле слова. И фраза "a group substituted on an alkyl, ... at any atom of that group" действительно лишена смысла (для halo, hydroxy, oxo, nitro).





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Note added at 5 hrs (2012-08-10 19:25:31 GMT)
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Еще раньше фраза:
The term "optionally substituted" means that the specified group or moiety, such as an aryl group, heteroaryl group and the like, is unsubstituted or is substituted with one or more (typically 1-4 substituents) independently selected from the group of substituents listed below in the definition for "substituents" or otherwise specified.

Опять "заместители" в обычном смысле слова.



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Note added at 14 hrs (2012-08-11 03:56:32 GMT)
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Возможно, хотели написать:

The term "substituents" refers to a group substituting any atom of alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heterocyclyl, heteroaryl, acyl, amino group.
Заместитель - группа, замещающая любой атом групп алкил, алкенил ....и т.д.

Тогда все складывается:

1) R2 is aryl, e.g., a substituted aryl

2)The term "optionally substituted" means that the specified group or moiety, such as an aryl group, heteroaryl group and the like, is unsubstituted or is substituted with one or more (typically 1-4 substituents) independently selected from the group of substituents listed below in the definition for "substituents" or otherwise specified.

3) The term "heteroarylalkyl" refers to an alkyl substituted with a heteroaryl.

4) The term "arylalkyl" refers to alkyl substituted with an aryl.

4) The term "alkyl" refers to saturated non-aromatic hydrocarbon chains that may be a straight chain or branched chain, containing the indicated number of carbon atoms (these include without limitation methyl, ethyl, propyl, allyl, or propargyl), which may be **optionally inserted with N, O, S, SS, SO2, C(O), C(O)O, OC(O), C(O)N or NC(O)**.


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Note added at 14 hrs (2012-08-11 04:24:10 GMT)
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И даже
5) Suitable substituents include, without limitation, halo, hydroxy, oxo, nitro, haloalkyl, alkyl, alkenyl, alkynyl, alkaryl, aryl, aralkyl, alkoxy, aryloxy, amino, acylamino, alkylcarbanoyl, arylcarbanoyl, aminoalkyl, alkoxycarbonyl, carboxy, hydroxyalkyl, alkylthio, CF3,... cyano or ureido. In some embodiments, substituent can itself be optionally substituted. In some cases, two substituents, together with the carbons to which they are attached to can form a ring