Table 2.

Number of Various Synthons Types Generated for Reaction Sequences A and E

#	Method	Reagents	Number of Synthons
			No Reactivity Features	With Steric Features	Total
1	A	1	467	196a	663
2		4	6,706	1,271	7,977
3		5	5,451	1,063	6,514
4	E	2	41	0	41
5		3	52	0	52
6		8	17,944	550	18,494
7		9	26,434	646	27,080
8		10	807	0	807

^aWith steric hindrance at the free amino group (103), the protected amino group (82), or both (11).